Anyone explain the differences between head units?

[kodiakz]

Humm this, just add the N2 to your existing setup as a dvd player/monitor and output its audio/video to the D1 and to the rest of the system from there. However, since you already have nav, there are many other units that will do what you want as well or better for the same or less money. I would look at the Kenwood and Alpine units as they will play dvd's and have excellent picture quality to boot. Look at the Kenwood KVT717dvd--I feel that nav aside, it is a better unit than the N2 and will cost you much less. The Alpine DVA901 is tops, but it is not cheap. Just food for thought. I would post some pics, but we still have some of the dash torn apart finishing up the radar and alarm/start. Will post when all pretty again!