I have one, an early model, and spent a fair amount of time with the developers (former 18B guys) at Rifles Only on a couple occasions. The design was purpose built to reduce back pressure and thus the increased cyclic rate and wear on the M4 system. Other parameters were secondary. To that goal, they seem to have done well. It suppresses well, on par with several other cans I own. Not the best, not the worst. Blowback is minimal. While I don’t run FA in my guns, I did run some full auto with their cans and it seemed to accomplish their stated goals. I find it does not degrade the accuracy of my rifles (though I admit it does not see use on my bolt guns). The major drawback in my experience is that it is long and heavy. They do have a non-overbarrel model, which may be lighter and shorter. They also were not successful in their plan to register only one part of the modular design with BATFE, so that took some of the uniqueness of the design away. I won mine at a match, so I certainly have no complaints about price vs performance. I don’t think I would have paid retail for it, though, in all honesty.
My thoughts....
Doc