Ha i am an ASE master mechanic and a senior Lexus tech and i took one look at the Viper 5902 system an said screw this. I just got done installing the AVIC navi unit and that wasnt too bad took me 4 hours. I really dont feel like stressing myself out for 10 hours getting this thing done.... so yeah im opting to have Best buy do it for a couple hundred. In this case id happily pay 200 bucks to save myself that headache.