I use a TomTom XL V2 Western Europe £130, on my TA 700, sucker sticks nicely inside the screen above the rev counter, avoiding most of the climate conditions. The V2 model seemed to have had a better suction cap, more suited to my bike than other models I looked at.
If it rains, it fits in a cheap clear, pvc topped tank bag.
Around xmas, a few stores where doing a TomTom special, text to speach
Full Europe for the same price I paid for the W Europe

Mine has only 1Gb of memory, which I belive effects which maps I can use looking at their web site.
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