I got the tower battery and charger several years back for like $20 and I charge it 2 or 3 times a year...and I have used the charger to charge up my 50cc scooter battery, took about the same amount of time for the tower battery around 5 hours or so...but I generally fly smaller engined stuff,,,it has started a .65 4-stroke and a .40 2 stroke many times... but mostly .049-.15...if I fly mainly larger stuff, I would go lawnmower cheaper battery as opposed to motorcycle battery,,sometimes you can find them on the bay for $30-40, but the local auto parts store probably has a mower batt for $20....Rog