I put a red top Optima in my Duster some ten years ago. I had problems starting the car this past summer and after checking various other things, came to the conclusion it must be the battery. The car sits around a lot, so that plus the age of the battery, I figured it must be time. I took it to the parts store where I always go and they said it seemed OK, but since I'm a regular they would warranty it for me anyway.
Well that didn't fix the problem, so I did some more checking. Came to find out I had a bad connection at the firewall harness plug, so it wasn't the battery after all. I later talked to one of the parts store clerks, and he said my old battery is now in his car, and still going strong!
That's a 10-yr old battery we're talking about! Most others seem to fail in 3-5 years, so for the cost, I think the Optimas are a bargain!