I'm a Garmin guy for several reasons, not the least of which is that's the interface I'm used to and like, but also because I know it's the most accurate as far as mapping and routing goes. I'm also in a van and don't need most of the truck specific features, and my carrier won't put HAZMAT on a van, so I don't even need that, anymore. But if I did, I'd go with the Rand McNally despite being a Garmin guy (because the Garmin version of a truck GPS is not that good).
I also have the software PC Miler on the laptop, which I use a lot, too. I also use Google Maps, both on the Web and the Google Navigator on the phone, plus Streets & Trips, you name it, I use all the tools necessary. Most people do the same thing. Don't rely on a single mapping or routing program too heavily. I've got a load that delivers in the morning, for example, that only Google Navigator on the Droid or Google Maps on the Web can locate. I can locate the same point on the Garmin GPS, then have the Garmin to the navigation.