from their cycle data you should need to for a good long time. i just got a set myself and ya, their expensive and ya they dont have the same reserve capacity but i can get two full days of trolling on them. i hardly ever use my outboard anymore. i like the way they discharge too. they give it all they got till they aint got no more.I wont buy anything else ever again
for the guy with the bad battery if you got the money, get them. if you dont, dont. i would put the money into the best trolling motor i could get first even if i had to buy batteries every year. powerdrive, autopilot, & co-pilot are the best invention since the fishing pole.