Had the Vaistech SLI I bought during the group buy installed in my '06 LS (Mark Levinson). Tweeter did a great job with the install (one guy there has done a few cars for me). SLI unit installed behind the head unit / iPod installed in the sliding tray below the head unit (so it's easy to access if you want to go to simple mode and control from the iPod itself).

It's great to have ready access to 30 GB of music, plus podcasts / books on tape.

Takes a little bit of effort to setup playlists -- I start each playlist with a sequential number (01 to 99), and 01 to 12 link to the 12 push buttons displayed on the NAV screen in MiniDisc mode. Put your next favorite above and below the 12 so that they are easy to scroll to.

Best bang for my audio buck that I've gotten in a long time.