I doubt whether google maps will keep up with you moving at motoring speed Booldawg or provide detailed driving data. If your current Tomtom is up to date and in good nick, as in having the free software upgrades installed, I would go with Tomto Go.
You have another option - the Co-Pilot app on your smartphone. I've been using it for years on an old tablet and find it much better than my the TomTom I used before that.