The rechargables are a pain.The AA or AAA last longer. You just need to turn them off when not using them.
What sort of range are you looking for? We use them for parking. The spotter talks. The driver listens. Maybe if one of us is going wandering around the CG. Sometimes use them in a big box store. Saves hunting each other down.
Knowing the limitations of the radios helps. Both of us are ham radio operators however there is little point in having something expensive with a range in miles when a 1/4 or 1/2 mile will do.