I use a luminator on the bars ( battery pack just weighted at 350g = 1/2 a bottle of water) and a XLM V2 on my bonce shed loads of light and I do not use the luminator on full cos there is no neeed
The luminator has quite a spread of light where as the V2 is more of a spot light and they complement each othere nicely
Smudge at mtbbatteries will supply smaller battery packs if required just ask him