I need another hobby like another hole in the head but here goes anyway...  Doing my homework before purchasing an AR-15 reading here, there and checking out what's on my local gun shops shelves and am leaning towards a Bushmaster, Armalight or Rock River at this point.  Fully planning to mod whatever I end up with as I've done to my hunting rifles which usually includes bedding, slimline muzzle break, teflon finish, 3 lb. trigger, etc...  I read an article where the writer tested 7 or 8 AR-15's and the trigger pulls from the factory were anywhere from 6.5 - 8...  I've gotten used to 3lb. triggers on my hunting rigs and am assuming I'll be more accurate with an AR with a better-than-stock-trigger...  What's the general consensus on triggers for AR's, have the stock triggers machined, replace with aftermarket, or buy the rifle with a competition trigger already fitted...?   I'll not be doing much long range stuff with this rifle nor hunting with it other than the occassional Coyote in my yard...  It'll be for PD in addition to my G23 sidearm and mostly a .223 / 5.56 plinker...
SMD223

       There are various aftermarket triggers from mild to wild with cost as you would expect.
       I have messed with some of the fancy ones and pretty much setteled with the Rock River National Match (RRNM) which will drop right in,has no adjustments or fitting required,and will end up around 3 1/2 lb.
       Many suppliers will be selling them for $99-$110,If you know someone who has a account at Brownells I believe they are around $75.
        You can't really go wrong with Bushmaster,Rock River,or Armalite. Do some reading here and try to find a model that has the stuff on it that you want.I have some Stag parts and have been impressed with that company also. Colts are nice but pricey and they have some issues with parts being non standard vs all the rest of the brands.

       Welcome

Weclome to the addiction.  

Considering the triggers you are accustomed to, I suggest looking at the Timney/POF trigger.  It is a "drop-in" unit so it is very easy to work with and the two I've palyed with in gun shops felt very nice.

I've heard very good things about the JP trigger, and felt one this past week.  It's light, has zero creep, and barely moves when it goes off.  It can be had from 3-5lbs depending on which springs you use iirc.  They make a drop in fire control group (hammer, trigger, sear in one unit) but they say the feel isn't as good as the standard version.  It's $180 with the hammer and oversized anti-walk pins, or you can send it to them and they'll install it for $220.  

You are going to have to decide first whether you want a single or 2-stage match trigger.  Then you are going to have to decide if you want one that uses setscrews or has specific adjustment capability.  Some people don't like the idea of a screw that could come loose.  The single action Accuracy Speaks trigger is mostly improved geometry with no screws.  It may likely need a bit of fitting.  There are many 2-stage match triggers, some of which just drop in with no fitting or adjustment.  If you are going to use it for PD, you may not want a very light trigger.

Remember that if you work on your trigger, stock or not, removing surface metal may remove the hardening requiring a heat treatment to restore.  Go lightly.

Over the years I've tried most of the brands mentioned in this thread. Any of them can usually be made to work. I have a rifle similar to the one you want a trigger for. Of course reliability is likely a big issue. I've had great luck with a hand fit Accuracy Speaks brand. Screws and adjustments have always worried me if reliability is paramount. Now I've got McCormicks in my rifles because I keep having excellent results with them. There's some very interesting tech info in the McCormick website on AR15 triggers that might be worth reading to assist you in your choice, whatever trigger you go with. As a matter fact, due to some of the education I got from reading that info one of the industry members thought I was some sort of expert or something, HA!

Depends on what you want to spend to get the trigger that you want.  For the cost the cheapest, and quickest way to a reduced pull trigger is just using a reduced power spring kit.  It will get you down to 4.5 or so pounds for the least amount of money. It may get to 4 if you have a well worn in trigger kit. Anything more starts costing allot of money.