I belive the Deluxe includes maps for all US regions, where the regular version includes only one region. Also it includes the car kit.

I bought the deluxe version a few years ago and got the iQue 3600 to replace it a while later.

I found the GPS V to be more rugged (spash proof, regular batteries) but since I mainly use it for driving navigation, I really liked the color display and voice navigation in the iQue. Not to mention that the GPS V uses a serial port and has only 19 mb of memory for maps, so I was constantly changing cities. It would take 20-30 minutes to put the new maps on the device as well.

The iQue uses standard SD memory and I can fit most cities I visit on a cheap 256 mb card.