Went searching for a replacement battery today.  Wal*Mart doesn't carry Optima batteries, neither did Napa.  I finally found that Advance Auto Parts carries them, though the price was a good deal higher than I seem to recall paying at Pep Boys a year and a half ago.  Sam's Club was cheaper for the other sizes, but they don't carry Group 78 Optimas and apparently can't get them.

First I brought in my old battery for them to test.  The test was "inconclusive".  They offered to hook it up to a charger for 8 hours, but I figured if it's "inconclusive", it's certainly already lost a good portion of its lifespan.

I asked about warranty replacement, and the guy said I'd have to take it to where I'd bought it, Pep Boys.  Which the nearest appears to be in Wichita, Kansas, 260 miles away as the crow flies.  So much for that.

It was only an extra $20 for the Optima Yellow deep cycle battery, so I decided to go with that one.  It doesn't have as much cranking power as the Red and the warranty is shorter, but it's got a higher power reserve and can withstand full discharge cycles without damage.  It's still about as many CCA's as the stock Delco battery, and deep cycling a Red battery technically voids the warranty anyway.  Until I can find out what's causing the power drain, this battery is probably the best bet.

I also had to pay an extra $10 to get one with those damn GM side terminals.

This battery is FREAKING heavy, about 45 pounds!  Much heavier than the Red, which itself was heavier than the stock Delco.  I almost sprained my arm picking it up, I wasn't expecting that much weight.

Hooked the battery up, everything came on right away, and the engine fired up the instant I turned the key.  I still plugged it into my new battery charger and ran it through a full charge cycle.  Although it was a new battery, it had been on the shelf for several months, so it was probably a bit low.  Because they have a higher reserve, it takes much longer to charge with the alternator, hence my desire to top it off.  I also ran the charger's alternator test, just in case.  No problems detected, even with interior lights, headlights, radio, GPS, radar, and fans
all turned on.

Now I just need to find a new maintenance charger, preferably one that can plug into the cigarette lighter instead of needing me to pop the hood every time I put the car away.