I got a CMMG lower from Aim a few months ago. Stampings are nice and crisp. The front and rear push pins were snug but have worn in(probaly the finish on the pins itself) Other than that Its as good as any other one i have used (bush,stag,dpms)
I have 6 CMMG lowers. 2 built into rifles. the rest waiting for the day I can build them as well. I own 3 CMMG uppers. I would not hesitate to buy another. BBLs, all have functioned flawlessly. I have one with around 6k rounds through it in in a NFA weapon. No complaints.