sorry to hear your 600 went bust so quick...

well... I'm using the Montana 600 on my KTM handlebar with the Garmin bracket and some rubber vibrating absorbent blocks mounted to it... working ok so far...

But.. yes.. the Montana is complaining that it can't find the right Garmin battery.. during the high frequencies vibration I guess... the battery is way to sloppy in it's compartment..