I just got a warranty replacement on a red top optima I bought about a year and a half ago. It was free this time, but next time I will go odyssey or whichever battery has the best warranty at the time. I just ordered a dual battery tray from Columbia Overland so we will see...

 

I had a yellow top that died after being parked for a few days so I went to a blue top and yes it fits. A bit pricey but thus far worth it.