What is the primary usage model you anticipate for this armor? What primary ballistic threats do you think you will be facing?
Those US Palm PC's are ok but the plates they sell are pretty heavy. Personally I think they're OK but kinda minimalist and limit your versatility.
I run an Eagle releasable plate carrier. It's not a CIRAS which is bigger with more coverage and bulkier. I run Dyneema plate backers, Ceradyne 6X6 side plates, and AMI TAC3S Multi Hit Level III+ plates front & back. It's as comfortable and almost as light as the Mayflower APC it replaced. It's not as specific about plate cut and sizing as the APC and the MOLLE Webbing is stronger. It has a QR cable like the CIRAS and it'll fall away from you with a strong tug.
The AMI plates are hybrid steel and compressed Dyneema/UHMWPE. They weigh about 7.5 lbs each. They'll stop both 55 grain M193 rounds that can zip through solid steel plates and M855 green tip that will perforate UHMWPE "plastic" plates like butter. These plates will take a shit ton of rounds and physical abuse without a blink or degradation in protection. Ceramic plates need to be x-rayed yearly for cracks and will shatter after taking a few rounds or if dropped on a hard surface. These plates don't have those problems. They'll also stop threats above and well beyond the NIJ Level III standard. I've seen a plate that stopped a solid copper alloy .338 Lapua Magnum round fired from 100 meters. There's a lot of deer rifles out there that are a hell of a lot hotter than a 5.56 or .308 so that knowledge is comforting to me. AMI will sell them to civilians with a CCW. They ain't cheap though. I think they are $550 or $650 a piece. There is a .mil or LEO discount if you fall into either category.
I bought everything but the Dyneema plate backers slightly used in the EE or on other online B/S/T forums for less than half of what the stuff would cost new. I have less than $1,000 in the setup. All it takes is time and patience to replicate this approach. I've helped a bunch of like minded friends buy similar setups for not a ton of cash.
My 1st PC was a Eagle PC. It was OK but starting out back then I was in the "I want to carry everything including the kitchen sink stage" It didn't have that much MOLLE space. It has inner cummerbund narrow straps with fastex buckles and an outer MOLLE Cummerbund with a flap in front. It was moderately "comfortable" as far as body armor can be. The PC is not quickly releasable. The PC is made from 1000 denier nylon. I never had any problems with wear and tear on this vest or the MOLLE webbing. Eagle has since been sold and their quality reputation may not be what it once was.
I replaced it with a Eagle CIRAS. It's a big bulky vest with tons of room to hang crap on. You can literally turn yourself into a Tactical Turtle with add on Shoulder, neck, bicep, and groin armor. It's got a lot of adjustment for various body types. Sizing on these runs big so try one on if you can or get one size smaller than you'd get normally with any other vest. It has a slick wide elastic inner cummerbund with velcro fastening and an outer MOLLE Cummerbund with a velcro flap in front. It was less "comfortable" than the PC because it covered more area and was heavier and hotter. It wore better because of the adjustability and the wider inner cummerbund. The CIRAS is also Quick Releasable by pulling a QR cable. The vest will literally fall off of you. The CIRAS is made from 1000 denier nylon. I never had any problems with wear and tear on this vest or the MOLLE webbing. Eagle has since been sold and their quality reputation may not be what it once was.
Getting older and a tiny bit wiser I decided there's an awful lot of shit I do not need to carry on my plate carrier. To wit, I traded for a Mayflower APC. It's made from 500 Denier Nylon and is a helluva lot lighter than the Eagle PC or CIRAS. I gave up a little bit of durability for a lot more comfort and maneuverability. It comes with a built in three mag kangaroo pouch in the front cummerbund flap. The cummerbund has pockets for side plates although you'll need to find some really thin 6X6 plates to fit. Standard Ceradynes are way to thick. The new APC's come with fastex swift clips so you can take a Mayflower chest rig and just clip it on the PC and go. That way you can run the APC as a low pro PC under concealment if you have to or transition to EBT System Shutdown Apocalypse mode in a minute or two. It beats the hell out of threading MOLLE pouches if you like the pouch layout of the chest rig. I have had some minor issues with MOLLE webbing stitching coming loose on my APC. The APC is a lot more limited on plate sizes and shapes that it will accept. Mayflower/Velocity makes some EXCELLENT soft armor and lightweight plates if you have the cabbage. They will fix any problem you have with your gear PDQ too. The APC is not quick releasable.
-----------------------------------------------------------------------------------------------------------------------------------------------------
Soft Armor
-----------------------------------------------------------------------------------------------------------------------------------------------------
Dyneema laminate armor is the lightest, thinnest, most flexible, comfortable, and expensive soft armor you can get right now. Kevlar/Twaron woven panels are thicker, heavier, stiffer, and generally about 1/3 to 1/2 the price of comparable level Dyneema panels. Kevlar/Twaron is usually woven panels. Dyneema can be woven or unidirectional fibers in layers oriented at 90 degree angles. Woven Kevlar is better at stopping contact shots than Dyneema. The tiny thin fibers in the Dyneema can sometimes melt and be blown apart by the heat and flash of a contact shot and let a bullet that it would normally stop easily penetrate the panel completely or much further than normal. Dr. Gary Roberts (DocGKR) has posted extensively on this subject here and on other gun forums if you want to get into the weeds of the issue.
Whatever kind of soft armor panels you get make sure that they are fully enclosed in a waterproof shell. Water soaked soft armor will suffer from seriously degraded performance and a decreased service life. Also make sure your soft armor is stored either flat or so it won't get a sharp fold or crease. It can cause the armor to fail to stop a hit in the creased area. Make sure your soft armor panels are cut to the correct size and shape to fit your vest.
Do not buy Zylon vest panels. They are shit panels that have got a lot of people shot. Several manufacturers got put out of business over that debacle. Don't buy really old, stained, or creased panels either.
-----------------------------------------------------------------------------------------------------------------------------------------------------
Hard Armor Plates
-----------------------------------------------------------------------------------------------------------------------------------------------------
Solid steel plates are great for cheap Level III hard armor. They are very thin and usually fit in most plate pockets easily. They'll usually stop a ton of hits and other abuse. There are a few negative points though. They are heavy as hell. They need to be placed inside a kevlar or multi layer ballistic nylon spall bag to catch bullet fragments and prevent them from seriously wounding the wearer in the face, neck, arms, or groin. The outer covering of the vest is not a substitute for a proper spall bag or covering. The better plates have a spall stopping layer of nylon or kevlar laminated to the plate with epoxy or a bedliner type compound. A consistent and even heat treatment of the steel plate is CRITICAL to the plates ability to work. To soft of steel and it'll let bullets through. Oddly it's usually the 55 grain and lighter stuff that gets through. If the plate is to hard it gets brittle. These plates will shatter when they take a hit or dropped hard. Bubba built steel plates can have these heat treat problems around the edges where they were cut out of the original steel sheet. Bare steel plates will wear through the fabric of the plate carrier pretty quickly. Another good reason for a spall bag.
Ceramic plates are what the military uses and the current state of the art tech for stopping advanced armor piercing threats. Aluminum carbide plates are the older and cheaper version of this tech. They will be thicker and heavier than a comparably rated set of Boron Carbide plates. You can get a very wide variety of ratings in plates some are NIJ certified and some are not. Some plates far exceed the NIJ rating system. You'll usually see these marketed as Level III or IV + or multi hit. There is no NIJ test for the "+" rating. Some of these plates will have a Level III or IV with the letters "ICW" after that. ICW means that the plate is only rated at that level when there is Level IIIA soft armor behind the plate. Weight per plate can range from about 3.5 lbs to about 10 lbs per 10"X 12" plate depending on technology used and ballistic rating. Ceramic plates should be X-rayed annually to check for cracks or after a drop or hard impact. A ceramic plate that has been shot should be immediately discarded and replaced. Several batches of USGI ceramic SAPI and ESAPI plates have been recalled for cracks and failure to pass batch testing. Beware buying USGI plates on EBAY and other sources because they stand a high chance of being; A.) Stolen USG property B.) recalled plates that may fail if you get shot. Buy from a reputable source. Ask lots of questions. Pass on the deal if you get no or bullshit answers.
Polymer plates made from Ultra High Molecular Weight Polyethylene or other wonder polymers are available. They are usually very inexpensive, crazy lightweight at around 2-3lbs each, and they even float in water. The downsides are they lose some strength at high temps commonly encountered inside cars and trucks here in the South during the summer months. They can be thicker than steel or ceramic plates which can make them not fit in some carriers. The biggest problem with polymer plates is the fact that to my knowledge none will currently stop a steel cored projectile like M855 green tip or Chinese Steel cored 7.62X39mm. Both are very common rifle threats encountered worldwide and here in the US. They are excellent at stopping a wide variety of standard lead cored rifle threats well in excess of the NIJ standard. They can also absorb a huge number of hits without failure unlike ceramic plates.
The last category of hard armor rifle plates is Hybrid plates. They are made of a variety of the previous three plate technologies. The AMI TAC3S is one example of a Hybrid plate. Hybrid plates allow the manufacturer to use the best features of each ballistic technology to tailor a plate for a specific threat and usage model for maximum performance.
-----------------------------------------------------------------------------------------------------------------------------------------------------
Good reputable retail sources for armor for civilians
-----------------------------------------------------------------------------------------------------------------------------------------------------
BulletProofMe.com
TriadTactical.com
OPTactical.com
Grey Group Training
Appalachian Training
-----------------------------------------------------------------------------------------------------------------------------------------------------
Good reputable Plate Carrier Manufacturers
-----------------------------------------------------------------------------------------------------------------------------------------------------
Blue Force Gear --- Local Georgia boys and top notch kit
Eagle Industries-----The old industry standard
Paraclete-------------Another old industry standard
SKD Tactical---------I Know a lot of people who love their PIG PC
MayFlower----------Great Lightweight Kit
First Spear----------A whole bunch of the original crew that made Eagle Industries the greatest started up First Spear. These guys have some very cool stuff that I haven't had a chance to try
TYR Tactical--------These guys have a "super" fabric they call Plomo Vires or some such. It's stupid light and very very strong and abrasion resistant. If I win the lotto or a rich old Aunt dies and leaves me a stash I'm calling these guys. I like everything of theirs I've tried.
Tactical Tailor----------------Another old industry standard. Not cutting edge tech but great solid gear that you can afford.
TAG---------------------------I don't know if you can still get it but they used to sell their Banshee PC complete with armor for less than $500 here a while back. That was a great deal for Joe Average on a budget.
There are others but that list should take you a while to go through. I've seen BFG PC stocked locally in gun stores here in GA around Savannah. I'm sure there's some places in Atlanta that do as well. If you ever get up around Fayetteville, NC look up Grey Training Group's Pro Shop. They have a ton of different stuff in stock for you to touch, feel, and try while you sip an adult beverage they can provide.
Hope this helps. Do you're own research and make an informed decision.