Reflex sights just work so well on a shotgun, it is a perfect match. The battery thing really isn't an issue with a little common sense. Most people could go two or three years without replacing a battery. So common sense says to put a fresh $2 name brand battery in your sight at the start of each season and don't worry about it. $2 per year is cheap insurance. Put a spare battery in your vest, now your doubly insured. Most of us spend $4 every time we pull the trigger. So $4 per year on batteries is nothing. These are lithium batteries. Lithium batteries can sit on a shelf for 10 years and retain 90% of their charge capacity. Just use name brand batteries from stores that turn their stock over often and a little common sense.
