unless you need the full all in one deal, get a good radio and an external GPS. Cheaper and better sound.
I have stock GPS/Sat radio I think it's a waste $1700 I think, can't go to garmin or tomtom for updates and no touch screen, have to pull over to enter info.
Apline and Kenwood makes good decks. HOWEVER you're dealing with viper amps and speakers so it isn't just a normal car drop in.