I have a TomTom GO 6200, and one of the first things I did was to remove the default Europe map (almost 7GB), and replace it with the United Kingdom and Republic of Ireland map (I can't remember the actual size, but think it is less than 500MB). This was free as part of the included lifetime maps (world). Obviously, if you intend to travel abroad, you will need to install relevant maps, but for UK use, map updates are fairly quick.My new unit includes WiFi as well as Bluetooth, and is able to download map updates directly instead of having to connect it to a PC by USB. All well and good, but it wants a map update out-of-the-box... 7GB! On my bandwidth and with a 10GB monthly cap?!!
Even if it managed to achieve the full 3Mbps for the whole download (as if), that would take nearly 7 hours.