Agreed, I have the BladeTech on a BOSS hanger for my AccuShadow and it's worked fine. For whatever reason it isn't an exact fit and the gun doesn't "snap" in the way my other Bladetech holsters do. But by using the thumb screws it holds it secure enough without impeding the draw. I wouldn't trust the retention for 3Gun, but it's fine for USPSA.
LS Holster in Colorado almost exclusively uses the BOSS with excellent success. They managed to fit the BOSS, G-CODE RTI and Comp-Tac PLM onto one platform so you can change them if you ever needed to. Where do you guys notice the Springer to be most popular? Divisions? Regions?
Fishsticks - you will find if you have a 1911/2011 that many makers have a hard time indexing the trigger guard because of the frame size, depends on who you use and what type of material they mold the gun in.