Old Review: It couldn't fit onto my threaded outer barrel, the hex screw was stripped immediately after being unscrewed with an adequately sized hex key. Sturdily built but isn't compatible with any of my 14mm threaded barrels.
New Review: After grinding away the threads on the attachment that were way too long, I managed to get the compensator to fit. I shouldn't have had to grind away the threads but it looks cool. Once again it is sturdily built and it doesn't scratch easily. Now it is 3 stars, would've been a 5 if it fit right off the bat. Hex screw still got stripped sadly, but the friction of it being forced on is enough to keep it in place.