On edit since I pulled the troubled Optima out: "2 new Optimas that come with our used trailer last April". These Optima's were not new 1 year ago. They were sold in June 2009. I moved them to the truck camper, it got used 1 day on batteries and 12 days on shore power last year. Charged overnight once a month in storage. 1 of these batteries is teats up.
2 - 6volt golf car batteries - powered the camper for 4 years, moved them into the 5th wheel last summer. They are still going strong. Water them once in a while and charge them in the yard now and again and use them.
They have roughly 130 days camping, about 40 days boondocking in the truck camper. Their latest abuse was a couple cold nights this winter powering the furnace which ran non stop from 9pm to 7am. They will be back in the TC for our spring trip.
I'll be picking up another pair of 6v's for the truck camper.