If you're talking about the permanently installed onboard type chargers, I've had excellent performance from the two guest chargers in my boat...one is a 2620 10 amp per leg that keeps the two trolling motor batteries hot...and the 2611 5 amp per leg that charge the cranking and auxilary bateries...just plug 'em in and FORGET 'em til time to use boat...goin' on 10 years and FLAWLESS...