Update

mine arrived : worth every penny (& some) Fires as well if not better than a broadside (that continuous connection is a winner). Button fires no matter where or how you press it. feels good in hand, not too chunky or cumbersome (like the scndrl) nor does it slip. Threads are as good as it gets.
My only neg would be I'd have liked them to have softened the engraving edges, they don't cut nor are the uncomfortable when in use it's simply an aesthetic. A second pass on the cnc to lightly chamfer would underline the fact you have just bought a seriously good mod for very little money. If I owned the copper or brass I'd use an abrasive to soften the edges, but I own this & don't want to damage the coating (which isn't going to chip in normal use that i'm certain of.)

TL;DR Its the tits.