Sat Navs

For the last 3 years I have been using a Tomtom Go Camper and found it excellent.  However, Tomtom have now stopped supporting it with map updates.  I am going to buy a new sat nav but am unsure whether to buy a Garmin 770 LMT-D or the latest Tomtom Go Camper.  The Garmin is £80 cheaper but I have read all 73 reviews on Amazon and a number complain that the device takes them down unsuitable routes despite being instructed to provide one appropriate to their motorhome or car/caravan combination.  During three years use, my current Tomtom has never done this, either in Britain or on the Continent.  Can anyone who has experience of Garmin camper sat navs please commenbt on their reliability in this respect.  Thanks, in anticipation.