I used for many years the Garmin 2610 with no issues on several bikes. Software become obsolete (v6), instead of upgrading i got the new Zumo 550. Unit is fast, sensitive and has buil-in MP3 and bluetooth. Fact is that it only last 3 days on the GS, even with Touratech vibration-free mount. It was shaking very bad and as a result one of the pins in the craddle was damaged, powering off the unit. I wonder how reliable is your Zumo on the bike (yeah I know K is not shaking that much). I updated the 2610 to same v9 software as Zumo and thinking to install that back instead.