Stero head unit question.

Hi Everyone. I have a 2007 Supra with the orginal Kenwood head unit in it. Over the weekend I got the Error E-05 code and now my Cd's will not read. So I figured out what the code means and now I would just like to upgrade my head unit. One with Ipod or USB would be nice.I have two Kenwood commander (kts-rc100mr) remote stations already installed. Are there any better units I can upgrade to and still use these remotes, or do I have to install the same one?

I figured out that you can only install the orginal 300 or upgrade to the 400 model. I guess if I want to upgrade I would have to put in new controls where my two commander units are. Since one of the commander units is installed next to my perfect pass, what are some other options I have for mounting a different control unit there in that space?