I've been messing with the Shaffer mount for a while now. So far, it is the best option I have found for my needs.
I opted for the right-side mount and put it on the left to kick the light back a little further for my short arms. This does cause a little more shadowing than I would like but puts the tail cap within reach and really lights up the front sight. I may end up taking the mag clamp off to reduce the shadowing a bit.