I recently bought the 62st and I love it:
The fact that the 60 and 62 series of GPS units take 2 AA batteries is a big plus, since I use them on and off the bike in a lot of different applications. For dual sport riding, being able to pop the GPS out of its mount and go hiking, geocaching, hunting, or just plain exploring, is a fantastic capability.
The 62ST comes pre-loaded with topo U.S., I added North America NT via Garmin's website. That combo is all I need.
Mounts for the 62 series are supposed to be out in December. I already have base mounts for the motos and bicycles. Meanwhile, with just a little imagination, I adapted the 62 to the 60 mount that I have and I've been using the 62 on everything I have.
Over Thanksgiving, I took the 62ST and the 60Cs out for a
geocaching experiment. The 62 locked on to satellites in just a few seconds, the 60 took much longer. According to My Garmin, I couldn't find map updates for the 60Cs, which is another reason I bought the 62ST. Make sure if you go with the 60 series that you can get map updates if that is important to you.
I'm very happy with the 62 series - whether or not someone needs the compass and/or the topo may determine what type of 62 model they consider, and they're priced accordingly.
As a side note for any GPS use for the bifocal crowd, for around 12 bucks you can get DeWalts impact resistant lenses with bifocal lenses built in. I use them on the moto and they work perfectly: