I too can vouch for the "other" types of batteries for a 24 volt system. I use everstart batteries from Wally World.... They are warranted for two years and if anything goes wrong with one or both...No problem...name a small town or street that doesn't have a Wal-Mart close by for making exchanges...Providing you keep the receipt... I keep my receipts in the small plastic compartment attached to the battery...That way I never lose my receipts and they are handy to get at.....