For what it's worth, my dad has owned a Magellan something-or-other for maybe 5 years and has had a very good experience. I know the technology has advanced hugely since then, and there are several good names out there, but it is something to consider.
I know TomTom had taken the lead in terms of worldwide sales, but I found
an article noting Garmin's recent surge into the top spot. The other brand supposedly worth considering is Lowrance (never heard of it before, myself).
Not sure how much digging you're willing to do, but
this site looks like a
wealth of up-to-date information.
Just reading about some of the newer models that are out there... so cool. For instance, the Garmin StreetPilot 2820 features hands-free Bluetooth calling functionality, 3D map/street perspective, real-time traffic and routing capabilities, comprehensive North America and Europe maps pre-installed, an extensive points-of-interest database, XM radio compatibility, XM NavTraffic service standard, USB connectivity, interactive 3.8" color touch screen, digital audio player w/ MP3 compatibility, 100% waterproof enclosure, lighted keys, etc.
The fact that it'd put you back a grand or so is only a minor deterrent.