Well, if we didn't, candle power forums has a complete subforum for headlamps, replete with lots of comments from aficianodos.

When you say AA headlamps, I immediately think of
Zebralight. Their models are single AA, but that just means that with a spare, you have double the run time. For me, runtime is the most important characteristic of any light - could I use it to hike all night or use in a cave on an extended trip?