[dmarv]

I was an Opitma dealer for 10 years. Very first one I ever tried went into my 911. Car had problems starting after that. Almost decided to change the starter before I checked the battery. Checked the battery, 9.5 volts. Charged it and the battery never got above 10 volts. Put back regular parallel cell battery and never looked back. I sold alot of them, my warranty rate was about 15%. That's about 5% higher than my regular battery line. Those numbers are somewhat misleading because of Optima's warranty policy, I'm sure I was warranting batteries I never sold to begin with. Only major problem I saw was using yellow tops in regular battery environments (i.e. always being connected to an alternator or generator.) Yellow tops didn't seem to last as long in these environments as Red tops. Optima rep said it was do to the battery design. Yellow tops are best in a true Deep Cycle environment. These are applications that do not have a supplemental charging system (RV, marine without alternator or generator, etc). Just my 2 cents.