I just gone done installing a new Alpine headunit w/ XM and iPod connectivity on my 06 SR5 with the base audio package. The sound improvement is nice, and I haven't even replaced the stock speakers yet. I spent maybe 2 hrs doing it, but only because it was my first time taking a 4th gen...
Yeah, I guess it would make the 3 hr drive out there more tolerable... I'm in the process of putting in some headrest monitors, but I think I'm gonna do a not-so-permanent mount... Depends on what I can come up with.. Plus, I'm afraid to cut my headrests!