+1 on the 550. I couldn't do the trips I like to without it. I have never figured out how to read a map on a bike at 70mph. With the Garmin, it just tells me where to go. The main reason I bought the 550 was because of it being water proof.

A few years ago I got into IFR (for you non-pilots, I couldn't see ****) conditions and all I could see was the Garmin, glasses too fogged and didn't know my way around. It led me right back to the hotel I was staying in, in Maine.

 

I have been using a Zumo 450 for 2 years and wouldn't leave home without it. I wish I had bought the 550 for the XM satellite radio and when this one bites the dust I'll buy the new 665 with the XM feature.
Ride safe.
Steve.