I decided I was not going to buy another NAV disc from Toyota for $300. So I am in the process of removing my factory NAV unit from my 2008 Crewmax Limited and replacing it with a Kenwood DNX-9140. Have a friend who works for Kenwood so I could not pass it up. Now I am wondering what I am going to be giving up by removing the factory NAV system that is driven from a DVD map disc to a hard drive based NAV system with Garmin maps. I am excited but apprehensive. Is this going to be a easy or difficult install ? Did I make the right decision ?.