I hear good things about all three. I bought a RRA ATH in .223 Wylde and bought a 6.8 Coyote Carbine upper to pair with it. I'll post a pic tomorrow but with Federal Fusion MSR 115gr it will shoot 5 shot 100 yd groups inside .75".
Edited by QuitShootinYoungBucks (02/16/1609:01 AM) Edit Reason: Add pic
Check out Bison for the upper parts instead of PSA.
I hear their parts and uppers are good. My personal experience is they have the worst customer service. Don't answer phones or emails after they have your money. They promised 4 weeks on an upper. 10 weeks later with no return phone calls or emails, I cancelled my order and got my money back. People had to publicly shame them on the 6.8 forums to get a response. I would have been cool waiting if they just would have communicated with me.