I been very interested in TT, but am confused exactly how the map upgrades works..i know about the MapShare program..is that a limited service for a year then expires? and does TT have its own map update software seperately or does it go with mapshare? Becuase wonder if 4 years down the line will map updates be free or i would have to pay if i wanted updates.. if anyone can clarify tom toms map updates services that would be great. thanks