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...when it works. I'm on my second replacement. So I now have over $1000 into the Zumo 550 line. Reliability is not there. Why would I spend money on any additional Zumo products? Makes it hard to justify the expense of a new Zumo.
Not sure why you're having problems? I have had my 550 since 2008. 2- 8000 mile trips and many shorter voyages both on the Guzzi and in the car. Probably 25K total. Its gotten beaten up, left under the car seat for months in the hot sun, rain storms on the bike, etc. I also use the XM antenna when I get bored singing to myself ::)The only downside I guess is the limited map memory. I've had some issues over the years with map updates because I didn't have enough internal memory. I'm sure the newer models have solved that.