I tried to return my fried Optima under warranty and Sears stopped carrying Optimas. Probably because they are POS's. I upgraded to the new Die Hard Platinum. It is supposed to be more vibration resistant, faster recovery when drained, more deep cycleish etc... and it is a 4 year replacement on it. Only cost me $50 after the credit from the Optima.
I also tested the OBA and all works perfect. The new output hose doesn't even heat up, at least not for the 5-10 minutes it was running.