I'm really not sure if this is the right thread or not for this question, so forgive me if it is. My question is this. I have 1 mint Canon A1, and 2 mint AE1's, (35mm SLR for all you young guns) That I still shoot, especially B&W. They all use the PX28 style 6V batteries. The Lithium sell for 2x the amount of the alkaline. Can someone tell me the difference, e.g. life span etc...and are the Lithium worth twice the price? Thanks ahead, J.