A friend recently lent me his Garmin StreetPilot GPS unit and I am now hooked. Much like cell phones, I had absolutely no interest in GPS until I actually used one, now I wonder why I didn't use one sooner.

The StreetPilot is in my price range, but it is not designed for motorcycle usage. I like the Zumo, but it seems a bit pricey. The cheapest model, the 450, I've seen from $6-7 hundred. Garmin advertises a 400 model, but I cannot seem to find it anywhere. Anyone know who this is available through, if it is available in the U.S. at all?

Further more, if anyone has or knows how to safely mount and weatherproof a StreetPilot unit (R1100RT, K75C) that would be great as well. I am familiar with RAM mounts, but a sort of weatherproof case would be nice as that is my biggest concern.

Any suggestions?