I have five PSA uppers in .300bo, 9mm, 7.62x39 and 6.5grendel.
All are good shooters, no assembly issues.
I’ve also had a 7.62x39 10” upper from Radical Firearms for a few years. No issues with a loose barrel extension. Seems to shoot as well as my Draco AK pistol. But I hear bad things about their customer service. So if there’s issues, you’ll probably be wishing you were dealing with PSA.
I put a lower together for a co-worker who wanted his first AR. We’re local to PSA but they didn’t have anything in his price range. Another shop had CBC uppers, they looked good and with an FN bcg he had just a few bucks more than a PSA. I’ve not shot it so can’t comment on accuracy but he’s had no problems.
I also got an Anderson 10” 5.56 upper I put on a pistol lower. Have not shot it much yet but it keeps up with my BCM 14.5” upper.
I just got in a BCA 20” 6.5 Grendel complete upper this week, was just too cheap to pass on. Haven’t gotten it to the range yet but I gotta say, cosmetically, it may be my best looking upper. Appears to be assembled right. In 6.5 the BCA barrels can be hit or miss but some of them shoot surprisingly well.
I’d recommend any of these brands. PSA will have the biggest selection, if you want a lightweight upper w/mid length gas system, PSA has a budget setup.