zemike said:
Bad comparison, IMHO, that's like comparing cherries to watermelons.
30W XM-L vs. 9W XP-G
With such lumen outputs it's time to use oval optics.
Yes, in a lot of ways it's a totally unfair comparison. But, it depends on what you think the limiting factor is for your bike light. Size and weight of the light head, size weight of the battery pack, cost of the light. For me personally, the only limitation I really care about is the weight of the light head. Due to some neck issues, I simply can't ride with much weight on my head. I don't really care that much about any other factors. The 30W XM-L and 9W XPG light heads being compared here are the same size and weight.
With that being said, I seriously doubt I'll end up using a triple XM-L based light for myself. It's simply more light output than I really want. I haven't figured out a way to test this yet, but I suspect the triple XML light is so bright that your eyes actually dilate to compensate. If that's the case, it's going to make life tough for your riding buddies. I'm really just playing around with what's possible because it's fun.
I think the XML is significant because it's going to make it very easy to build reasonably sized light heads that can easily produce more light than anyone really needs. So, it's going to be interesting to see what happens. Will people start to care more about cost, size, weight, or lumens. The technology isn't going to be the limiting factor much longer.