As mentioned before, I don't think that it would be effective as a muzzle break since the bullet has already basically left the barrel, and the "port" wouldn't be effective in reducing felt recoil. However, with the angled front, I could possibly see it being effective for muzzle rise with the gas deflecting upwards off of the ramp and keeping the muzzle down.
They are pretty darn ugly, but IMO, the cool factor is up there. I might have to look around and see if I can make a Numerich order worthwhile.
Thanks for showing.