Hi guys! I'm in the market for my first SF LED. I have narrowed it down to the E1B, or the L1. By the output, beam shape, and levels they seem very similar. I am leaning toward the L1, since it comes on in low. The only thing I question is the tailcap. I have heard a lot about it, and I believe the same tailcap on the A2. I searched, but could not find a basic explanation as to how it really works. Can someone please explain?