Ive run the ebay solarstorm x2 (xml2 version) on the bars and a small quality single cell 18650 single xml2 emitter flashlight cable tied to my helmet for the last 2 years.
I bought 3-4 extra battery packs off ebay for the solarstorm (4x18650 cell packs). They are junk really but do the job and a cheap as chips. 1 battery pack failed, and the others deff dont have the capacity that they used to id say around 1-2hrs run time sticking mostly on Low. More like 1hr now tho with the old battery packs.
My helmet light was always my ‘main’ light and i always carried a couple panasonic 18650 cells in the camelbak so i was good for hours of riding, longer the ride the more cells id bring. (Bout 2hrs per cell run time).
Ive just gone all out, and bought an Exposure MaxxD and Diablo (at prices i simply couldnt say no too).
These lights are simply better then i could have ever imagined, the initial motivation came about as i was getting annoyed with the battery packs on my hadlebar lights and going to a 35mm stem meant id lost the one place i was happy strapping the battery packs (under the stem).
The MaxxD run times are more then adequate and the output is borderline rediculous. But the real game changer is the beam pattern. I really had no idea what i was missing but now there is no going back. The Diablo beam is perfectly matched to the MaxxD right across all the modes and there is no hostpot or artifacts in the beams just a huge wall if light everywhere, its daylight at night now!
The only thing that really does annoy me a bit is that i cannot change the cells, sure Exposure make battery packs you can plug into the lights to increase the run times (not an issue with the MaxxD but the Diablo really is only good for 1-2 hours max mtb riding without a extra battery pack, maybe 3hrs depending on the trails ridden) But if they had just intergrated a tall cap into the light body so you could just carry spare 18650 cells as i did with my other helmet light it would have easily become the best helmet light out there! I wasnt going to buy the Diablo at first until it came up at a great price too, but im so glad i did now given how flawlessly the beams work together.
Travis.