j/k...at my weight I couldn't care less. I would rather not have so much stuff hanging off my bike though. I'll probably end up getting a whole other lightset and a Y cable and seeing which works best. If the battery is only going to last 300-400 cycles then I might be better off using one at a time. I usually ride about an hour and half in the dark so that should work out. I rode 3 hours this am and the light did great! I saw things I never would have with my Blackburn Flea...the biggest of which were 3 deer just off the road in the bushes. I did throw my Flea on my helmet and now I don't need to use the backlight on my comp.
BUY THIS LIGHT NOW!
It is well worth the money.