Thanks to BITOG and all the knowledgeable and helpful guys 'n gals in it, I finally found out what the colorful and curvaceous automotive batteries in COSTCO are. They are the newfangled Optima's. Well, yesterday, I went to COSTCO to check out the same Optima's, and the helpful guy there told me they are not so popular nowadays. It is pretty much a "hit and miss" thing with hi-tech batteries, he said. Buy, install, and use at your own risk. Any opinions on this?