bubba I fought over pressure in my dpms ar10 back about 15 years ago. Ars weren't the craze then and there wasn't much help with problems. I eventually was told to put an adjustable gas block on it and paid GOOD money for one back then and it cure it. I know that psa had some over gassing problems too and some had some rough ramps but for 350 for an upper bolt group and charging handle nobody else comes close and it leaves a bit of money to fix it (if it needs it) I looked around on there sight and it is actually a very small percentage that have problems. As to compatability I will say this. I bought a psa lower so im going with there upper to insure compatability. that said my brother in law has a psa lower with a dmps upper and it runs perfect (his is a gen 1 lower and I don't know about a gen 2) But from what ive heard its really the upper that's changed not the lower. I do know that small things like take down pins and slide release are different on a psa but I bought a psa lower and a psa kit so its not concern. . Fit isn't perfect. You can see a bit of light between the upper and lower but its an ar10 not a Holland and Holland. Bottom line is theres no such thing as a milspec ar10. Bottom line is if you don't have one stoner built you don't have an ar10. That doesn't just apply to psa. It applys to all of them. Psa doesn't even call theres an ar10 so at least there honest. they also post warnings that there parts might not play well with others. I know im not buying a 2000 dollar noveske. Im buying a bargin basement gun. that said ive got 6 psa ar15s here that run just was well as my colt or stag. So for half the price of some other dealer whos probably buying his parts from the same distributor as psa ill roll the dice. Because not only is there not a real ar10 but theres not a company producing them (at least not for under 1500 bucks) that makes ALL there own parts. `I look at it like this. I paid 1100 bucks for a dpms oracle (stripped down entry level gun) about 15 years ago. Now dpms doesn't exactly spell high end quality. This gun will set me back about 500 bucks. That's about 250 bucks if we factor cost of living and go back 15 years ago. That's a slamming deal if you ask me. If it takes a 50 dollar gas block or a bit of Dremel work on the ramps so be it. Bottom line is if I could have bought that dmps for 250 back in the day. I would have bought 10 of them. Some day when the liberals make it tougher on us ill probably kick myself in the but for not buying 10 of them today. But im up to 12 ars now and my wife is starting to shake her head. She doesn't even know Ive got three more bare lowers in the safe.