I have a question about the audio system in my T4R. I plan on getting a new system sometime in the future but can I choose any system I want and have it installed and still use the controls from the steering wheel? What about the speakers? I would like to get decent speakers installed in the same place as the original ones. Anyone have any suggestions on who would be the most reliable like Circuit City, Best Buy? I know this may seem like a dumb question but I know nothing about this kind of stuff. But I need a good audio system and not go broke. Thanks for your time.