Aren't lithium primaries the same voltage as alkaline (1.5V)? Agreed about the voltage staying more constant vs lifespan and the better cold weather performance.

NiMh is lower and I've been burned by this in the past as I had several digital cameras that required the 1.5V batteries. My latest camera runs fine with NiMh and it's a big benefit to me. Glad someone finally decided to make that arrangement work.