I got this lower from PSA a month ago, fully assembled. My son is running it with his Radical Firearms upper, and it ran great for him his first trip out with it, about 240 rounds or so.
Today we took it to the range, and when I shot it, I noticed an issue. I tend to ride the trigger reset, and his did not want to reset after the shot. I actually had to push the trigger forward to be able to pull it again. Did it several times in a row. It doesn't do it if you release the trigger fully right away, only if you ride the reset.
We're going to open it up, clean it and test it with the lower removed from the upper to see whats happening.
I've heard that a backwards spring can cause this issue, but as I said, it was fully assembled from PSA, so I'm assuming they put it together correctly.