I am hoping to order one of those two later this next week and am wondering what the differences and pros and cons are? I am looking at the M3 multi-reticle btw. So far as I can tell, the M4 is AA powered and as such offers longer battery life. Is there anything else I am missing? I like the canted mount of the M3 better and will go with that one if there's nothing really extra that the M4 offers besides the battery life.