I have a 1990 Blazer, and when I bought it it had the Interstate battery in it as well as a Warn 8274 up front. One of the first things I did was remove the Warn and all the associated wiring as the winch was damaged, not connected and the bumper was ugly.
At this time there was nothing aftermarket wired to the truck, as I said unmolested. The battery it had was old, so I splurged for the Red Top Optima. I drove it for a few months before parking it in favor of my pick-up which is much easier on fuel. Two weeks later the Optima was dead.
I charged the Optima, and had no trouble doing so although I did notice it was different than a regular battery. On the 2 amp setting it was drawing nearer to 6-8 amps for the first hour or two. It did fully charge though.
About 6 months after I bought the Optima I installed the stereo, and used the factory wiring to do so. i drove it again for a couple of months, then it sat again...and the Optima died again. I charged it once again, moved the truck and disconnected it completely. A few weeks later I re-connected it as I needed to move the truck and the Optima was dead. This time I got out the multi-meter and checked voltage. 5.86 volts. I charged it once again, moved the truck and after letting it sit for a few hours I checked the voltage again and saw 12.6 (I'd have to go back and check my other thread for the exact number) I also charged the old Interstate which had been sitting dead in my shed for over a year. It read ~6 volts and charged to ~12.5. I set the Interstate in the engine compartment, disconnected the Optima and checked voltage daily for about a week.
Rather than repeat myself...here is the link.
http://coloradok5.com/forums/showthread.php?t=289847
I was seeing the Optima dropping pretty quick so I hooked it up to the Interstate with good cables and then charged at the 2 amp setting for 40 hours or so (unintentional, and a bit of a story...)
Both batt's read at 12.75 when I unhooked them and let them rest for 6 hours or so.
That was a week ago. I just went and checked them and currently the Interstate reads 12.59 volts. Not bad for an 8 year old abused battery that has more than likely seen a fair bit of winch time. The Optima reads 12.10 volts...
I can continue checking over a longer time frame if you want, but i'm not optimistic as I've already seen the Optima discharge over time when not connected.
FWIW I recently had to replace the batteries in my Pick-up. I was thinking of a pair of Red-Tops, but in the end I didn't have enough confidence in them. I bought a pair of traditional lead acid batteries instead.
