The solar strip only works when in auto mode or something, kind of a gimmick. I keep my 407C's and 507C's in manual mode 2 levels down from high, this gives me plenty of brightness for full sun and they don't wash out with a 1000 lumen weapon light. I change the batteries on my birthday and have tested the old batteries, they still had plenty of juice left.
I'm looking at a baby gun and the K version will be next on my list.
Mine is the 507C X2 I have idea what you mean by auto mode. I haven't changed the battery in a little over 2 years. I believe that it works when shooting in sunlight
