I gave it a good look but looking at the pics of it installed here:
2012 - TROY
Installed it looks like,a mess around the delta ring...the rail juts out beneath it, has a giant gap around the sight post...just looks rigged. For what they're asking, you'd be well on your way to just getting a mid length free floating upper.
Me? I have a carbine length non free floating and I went with the Midwest Industries drop in gen 2...not mid length for my model but it was half the price of the Troy, fits like a glove and looks great (also weights next to nothing)....food for thought...