You pretty much have to stick to the Garmin "motorcycle specific" GPS navigators if you want to be able to create routes on your computer (using BaseCamp or MapSource) and load them to your GPS, and/or upload your travel history from the device to your computer. Similarly, I think only the motorcycle-specific GPS units support music.
I suggest you investigate getting your 660 repaired. Perhaps contact Garmin via email or phone (they are in Olathe, Kansas) and find out if there is a Canadian service depot. Garmin is pretty good about repairing units for a reasonable price, and a repair will undoubtedly be less than half the price of a new unit.
The new units (e.g. Zumo XT) are very impressive, with remarkable screen brightness and lots of other features, but they are not cheap. On the other hand, if you like tech features and want the latest and greatest, get an XT and enjoy it. Whatever you do, don't get a TomTom Rider - I bought one for the ST 1100 I keep in Europe, and it is a sad substitute for a Garmin device.
Michael