I'm super excited about my first build. It is a 10.5" pistol build using a Radical Firearms upper and PSA lower. I started out wanting to do something a little at a time. That didn't happen. With the sales that PSA had and Radical Firearms it was time to jump. I started out with a PSA pistol lower. Couldn't beat the price. When I got it in I didn't like the trigger. I pulled it apart and did a little polishing. Added a reduced trigger spring kit. To my dissatisfaction it was a cut and bend job that I should have done myself. So I did it to my other AR with great results. I put a 1/4x28 set screw in the grips of both guns. I'm very happy now. I took the birdcage off of the radical upper and replaced it with the strike industry cookie cutter. That helped with recoil and rise somewhat. I have shot about 100 rounds through the radical with no issues.I sighted it in at 50 yards with a TRS25 red dot. The groupings are a little less than the size of a baseball.This might become an expensive habit. Now that the first build is done I might have to experiment with a upper tier rifle build.