I have run co -pilot and stopped with 11. I dont like whaqt it has become. Co-Pilot also tried to take me accros a bridge that would not support the weight of the motor home. If you depart from the route it selets, It nags you incessently.. I tried microsoft streets and didnt like that at all.
I have a Garmin Nuvi 5000 that the wife loves. 5.2" display. It has one drawback, if your 12 volt outlet goes off with the ignition you have to reenter the destinationor or store it in favorites first. I also have the same program running on my tablet PC so we both can looke at same thing when the other is driving. It recalculates almost instantaneously and doesnt nag you to death.
If you want a built in unit. You might want to look at the jensen radio VM9022HDN it has touch screen, hd radio provision for an additional camera and navigation by Tom tom built in. it can also allow you to plug in you ipod, or mp3 player, play music or vidoe from a cf card or memory stick and plug in a hand held camera. The downside is that the display is not bright if it is very cold but once it warms up it is fine.