Have just used Nuvi 550 for first time on 1700 mile trip to SOF and back.
Very impressed,it never lost satellite reception even in the odd city I rode through.
Very quick to recalc.
Battery life was 6 or 7 hours tops but with screen resolution turned right down to 10 or 20%.
I've just ordered a spare battery,for when I use it again on bikes other than GSA (which is wired up to battery).
All in all a bloody bargain for a smidge over £200.
Half the price of Zumo 550,same size screen,and half the bulk.
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