I love it when this question gets asked! Bottom line, for me anyway, this is a muzzle control device, and a damn fine one! It was designed to reduce the climb of the muzzle in multiple shots are in order, and I feel it does this perfectly. It is loud, obnoxious, and I usually have a headache afterwards, but its a good headache, cause I just got to shoot my gun! The range I frequent always asks me to go way down the line to shoot and I'm fine with that. The pounding of the sinuses I get every time the trigger is pulled lets me know I'm still alive.
Its a compensator; not a sliencer, not a flash supressor, not an A2 birdcage, not a ___________ (fill-in-the-blank). There are a ton of other muzzle devices anyone can get; all with a specific use. I have yet to find one that does its job better than the comp. in question. Like I said, its loud, its obnoxious, it hurts, but IT WORKS, and I love it!
I mean no dis-respect; this thing definately has its lovers and haters, just trying to give my opinion.