I got the Garmin 2620 and I looked at the Magellan because the Magellan was on sale at Costco. The Magellan was bulky and the mount was kinda... well, blah...
I went to Circuit City, brought up the Costco prices on their demo computer and asked them to match the price on either the Garmin or Magellan and they said "ok."
I ended up with the 2620 for $835. The best part about it is that the beanbag mount that comes with it works in almost ANY car- works beautifully in a Disco. The entire US is already on the little hard drive, so no downloading to it. I really don't use it enough to justify the expense, but it works flawlessly and finds even the most obscure stuff easily.
The Garmin also has a British English voice option... sounds more correct for a Land Rover.
There's a $100 rebate on the 2620 right now also...
edit: I think I was looking at the RoadMate 900 though... not the 700. If you want to save some bucks, the older StreetPilots are cheaper. There's supposedly a new Garmin that is a stripped down 2620 that will be $400...
