M5 aeroprecision upper - Aero Precision M5 .308 Assembled Upper Receiver

I have built several ar10 pattern rifles using aero uppers and lowers. I have been really impressed with the ease of assembly and quality of the parts. I also use the aero part kits for a smooth, trouble-free build-up. I would recommend these as the basis for any mid to upper priced build. You can absolutely spend more on higher priced parts, but except for brand name, you're not buying additional functionality or reliability.