The StreetPilot III is awesome...

Yes it is. I've had it for a little over a month now and I absolutely love it.

The voice prompting is just right, it warns you a few times before you get to a turn (i.e. "Turn left in 1.7 miles" .... "Turn left in 300 feet") so it's never too late.

I was originally going to get a V, but after thinking about it and realizing that the main reason I'd be getting one was for navigation in the car, I thought it better to get one that was better suited to be a "navigator," not having to look at it all the time, and just be (yet another) distraction.