I've done some upgrades to my base stereo and everything is much better. XM and radio is still a little disappointing, but Pandora and CDs sound great. This issue has nothing to do with the equipment as xm and radio have lousy signal quality.
Received 7/2/10: 11' GT base with 3.73,
Installed: Steeda CAI, SCT, Steeda tune, GT500 axlebacks, SVT leather wheel, Infinity Kappas, Boston amp, Bazooka powered sub, yellow fog light bulbs, dark front corner lights, GT500 splash guards, tint, SVE Drift matte 18"x9" wheels with 265/40s and SVE 1" drop springs, Koni Yellow, HP+ pads, brake duct coolers with CS front lower and splitter
Bought and soon to be installed: Edelbrock E-force stage 2
Stable: 14 SHO, 10 Road Glide