I'll tell you what, I own about 5 quarks and have the 2xAA and 1xAA tubes. I have both the R2 and XP-G versions as well. I have an Arc AA Adapter on the way for the peak head. I'll open a new thread in a few days and kick off a test... I gotta figure out why I can't upload pictures as well. I may have just have to do this the same way I ran the AAA tests and old school describe it. Anyway, I can drop some eneloops in and let's say single AA R2 vs XP-G vs Eiger AA XP-G? I don't have any other AA lights I would consider contenders for super duper runtimes... Anyway, like I said, a few days and I'll take this one on.