Any reason you don't want to run an optima? I've had great success with mine, but then again I don't have any major audio upgrades. Have been running an optima in my trans am for 6 years and still puts in work lol. They are pricey as well. I have duralast gold in everything else and for the money you can't beat the warranty.
2009 G8 GT PBM...... Not Stock