First I put all brass ammo through it, all 30 rounds, shoot slow one at a time then let it cool off while shooting my other firearms as my friend is shooting his toys.  Then I put through TulAmmo and ate them up without any issue then I ran another all brass through it with no issue.  Let it sat (got my arm too close to Diablo PWS muzzle brake and burned my arm...) for a bit while my friend was trying his brand new Vepr 12 and having issue cycling with cheap Walmart Remington shells.  I let him shoot 30 rounds of brass & Tulammo mix and went through no issue, then after it sat for about 5 minutes while I was playing with my 10/22 Archangel conversion rifle I ran 60 rounds using Surefire mag and no issue also.  My set up works really well, I am very happy with it.  I can't wait to shoot it again when my suppressor gets out of jail

My next build will be 7.62x39 upper with Spikes lower receiver pistol but 10.5" 11.5" barrel.

My setup as follow:

RedX Arms upper with SS 1:9 twist barrel

Ice Arms NiB BCG

Rainier Arms CH

PWS Diablo muzzle brake

ALG ACT FCG

Wolf hammer spring

Wolf buffer spring

Spikes H2 buffer

PWS pistol buffer tube

KNS pins

Phase 5 lower

Phase 5 BAD level

Core15 trigger guard

CAA grip

CAA MGrip2

Magpul XTM hand stop

ARMS flip up sights

Vortex SPARC red dot sight

Sig Brace

Edited: pic added

Current:

PWS Diablo is also a great muzzle brake, deep sound and very much manageable with recoil.  I have never fired an AR pistol and before today just by playing around with my pistol I thought it'll be quite different and hard to shoot but today I found out why so many people are going pistol route.  I am glad I build mine, love it....will be shooting more of it  I was thinking about getting Sig brace but after I shot my pistol I really don't feel I need it, it shoots fine the way it is.  

I notice when I was running TulAmmo rounds I get some carbon on my face so I will be staying away from cheap ammo but at least I know my pistol will shoot anything I put through it....

I need to sight my Aimpoint PRO, off to the right and low, so next time I am out at the range I will get it zero'd in.  Today a buddy of mine & I just went to make sure all of our firearms that we both purchased actually work as they should.  His Vepr 12 will not cycle rounds so he is pissed, but he ordered upgrade guide rod & heavier spring, we'll find out how it function next range day.  I still need to fire 3 of my firearms, we had to leave before testing them

You'll be happy with yours.....good looking setup you got there!

I will take another picture with it on and post it soon.

I love it, though I did not have any issue shooting with my cheek on the foam but this really makes the pistol feel better.  

I don't know if Gen 1 is going away soon so I made my move on one, like the way it looks and feels