As I wrote a few posts ago, I vastly prefer the Springer Precision hanger to the BOSS. Hearing @YVK talk about having to add foam to prevent bruising proves my point. Unless you need the cant adjustment the BOSS spacers allow, there's no reason to have a huge-ass piece of metal hanging down next to your leg. And, if you plan on doing ninja stuff while shooting, the Springer is absolutely the way to go.