Snooper vs Tom Tom Go Live Camper?

Hi, I'm a single mother with two small children and I've just purchased a motor home and used it a couple of times.  We LOVE it!  The only downside so far is my nervousness regarding getting stuck in a small lane.  I may have gone slightly over the top on size and our van is 8.7 metres long with a double axle so I'm quite apprehensive about manoeuvring it in tight spots.  For this reason, I have decided to splash out on one of the sat navs that are specifically for caravan/motor home users.  I have been looking at both the Snooper version and the Tom Tom Go Live Camper.  I have a standard Tom Tom at present and like the way it works.  Does anyone have any opinions/experience with using either?