I have searched and came up with the consensus that they are good to go....what does the hive say?

I've got one in .45acp, it's got the heavier buffer so I think that's a gen II. It's several years old so does not have the quick release buffer tube.

For a PCC it's heavy, very solid. A TNW feels lighter. The factory trigger feels like a good GI single stage, which is better than any other PCC I've shot.

Accuracy is great. No complaints.

However, the initial reliability was not good. Even after modding the mag it came with, it would occasionally bring a round up too high, jamming against the upper edge of the chamber. So hard it would force the bullet into the case. There's not much of a cone on the face of the chamber. I had to file down the upper edge of the chamber.

I think the angle of the mag is just a bit too vertical, but with some mag tweeks it's reliable. JRC recommends bending up the spring to put more pressure on the rear of the follower, which loses one round of capacity. Swapping the factory Glock mag springs with the JRC springs also helps, they're much stronger. Much more than Wolff springs. I also crimped the forward part of my feed lips to keep the rounds low.
Maybe other calibers aren't as finicky.
My modified mags run fine in my G21.
And SGM 27 round mags work if you drop a Kriss mag spring in them.

I also have a High Point .45 carbine, not as refined, not as accurate, but it did run right with no mods. Mags are just single stack 9 rounders.

And FWIW I also just picked up a PSA 9mm with the Glock billet lower, it ran perfect out of the box with unmodified factory Glock mags.

Many people, many opinions. I will just say this. I now have or have owned the following 9mm PCC's  Just Right Carbine, TNW Aero Survival Rifle, Beretta CX-4, Kel-Tech Sub9, Sub2k and Sub2k Gen 2. Marlin Camp, High Point 995 and 995 TS, RRA 9mm AR, CMMG 9mm AR, and something else I forgot...umm.

The Just Right Carbine (JRC) is one fine piece of work. I have the later model. I skipped the first generation as they worked out the normal bugs. I have had mine for a few years now and it is a reliable and accurate a 9mm carbine as I have owned. I like the fact it uses AR FCG;s and I have "tuned" mine for a few bucks by just changing some springs. Everyone who shoots it likes it. All the people I know who have one of the later ones like them. So, its a good piece. That said, its not the lightest of my group. It is, however, one of the smoothest shooting and most accurate.

I have an TNW ASR (Aero Survival Rifle). Its reliable and shoots fine. It is lighter than the JRC by a little. It shoots fine. I have the two stage trigger in mine due to personal preference. The trigger is OK, but not great. Its not well made as the parts fit loosely on their shafts and the trigger itself is narrow and doesn't have a good feel to it. If you want a lighter carbine it is a good pick. There are some issues however. Some have had problems. Some have had to be sent back to TNW. Mine went back for some TLC before it began running properly. Another issue is the quick change barrel. It can tend to work loose while shooting. It doesn't fall off but accuracy drops as you would expect. They have a "fix" in that you put a new hand guard on it. You fix the barrel coming loose but lose the ability to quickly beak down the rifle and fit it in a small bag or backpack.

The CX-4 is a Beretta. Chrome lined barrel, 100% reliable, very compact and light. Hard to find and not cheap.  Trigger is not great but there is a DIY trigger job that improves it.

The Kel-Tech should not be compared to the others. Its a special piece, made to be very light and fold up. Its more like a long barreled pistol than a PCC. Its not the nicest to shoot as its design has limits. Shoot one once and you will see. It has a special place however as it is so small and light and can be folded up and put away or brought out to action quickly.

The High Point works, period. Its not pretty. Its not a slick, precision German or Italian gun. Its American assembly line bottom dollar priced piece that will work now and tomorrow. Its cheap in price and you know it when you hold it. But it goes BANG every time and hits the target.

The 9mm AR is just that. Cold took a rifle made to be a gas operated 5.56 rifle and converted it into a blow-back 9mm PCC. Newer 9mm AR looking rifles are modifications of the original Colt design, some with improvements. Some even use Glock magazines.   I sold both my 9mm AR's. I had them running fine but the JRC would just out shoot them. The JRC was smoother. The Beretta CX-4 was lighter and smaller and would out shoot them. The TNW ASR was smaller and lighter and quick to break down and stow away. For me, the 9mm AR no longer had any advantage. For others it is popular. You have to decide what suits your needs and desires. Luckily you have many great choices now, so much better than just a few years back.

I had an incident with one when I was checking it out at my local dealer. I was holding it with my left hand when I slapped the locked charging handle to release the bolt. Since both sides were open and the bolt is close to the surface of the receiver, it bit my left hand quite badly. Have you had anything like that happen?

Beretta had stopping importing them a few years ago. Sometime near the end of this past year (2016) they started importing them again. They are now relatively easy to find and prices have dropped. If you pay more than $700 for one, you're being ripped off. I agree on how unsatisfying the trigger is. My spring based trigger gauge stops at 8 pounds, and it wasn't even close to releasing the hammer when I hit that limit. Sierra Papa seems to be the only source to make the trigger good.

I took my new one to a steel shoot this past weekend and it was a lot of fun.

Jard, Inc. makes two bullpup PCCs: The J67 and the J68. Both are kinda ugly, simple blowback designs. The J68 is really a J67 Gen 2 design. I bought a J68, but unfortunately it's been very troublesome. It was just returned to them for the third time, and they are replacing it. The feel of the trigger was excellent when I first received it, measuring out at 2.5 pounds. If the replacement is actually reliable I expect to have a lot of fun with it.

I am not a fan of The JRC, I bought one in 45acp. It has a big problem mangling brass, the extractor put a big notch in the brass making it useless. The JRC design is a PITB to feild strip and clean, it has 2 screws that you better not lose that connect the upper and the lower. Not fun to shoot, mangled brass, hard to clean, so I traded it in for a glock 41 and I am glad I did. For PCCs I like my AR15 9mm, my UZI, and my sterling. All of them are reliable and easy to clean IMO YMMV.

I seem to recall that when I first got it I might have had my hand pinched by it. I must  have learned not to do something as it never happens anymore. Actually the little ASR has been OK for me. Its small and light. I wish the trigger has a little better construction as its a bit loose on its pins. Works fine, just doesn't feel very well made.