TomTom here but look for one with
1) Built in WiFi - that way you don't need to plug it into a computer for updates - my only real problem was caused by a configuration issue in a new computer.
2) Enough memory or a slot for an additional memory card - Europe Wide maps and a few extra features soon fill up the built in memory on some models
3) Free for life map updates
4) Free for life traffic information (Saved our bacon several times when in areas we did not know and could have been caught in severe delays)
I have made a mount that hangs from the tonneau cover peg on the dashboard - keeps the windscreen clear. There are lots of examples around.
