If you have Never owned a sat nav for trucks its not to bad for the price,but if you have ever owned a TOT TOM then you will find it slow to route,small imput letters for putting addresses and post codes in,when you store your Favourite addresses they are not stored A-B-C they are random.
You also cant set a route unless you are on a road.
Also i have never been able to plan an alternate route, it always says non available even when i am at a roundabout and can go left or right it still says no route available?
The estimated time of arrival seems to assume that you can travel at 70mph all the way, (i emailed ProNav about this and they said that an update was in the pipeline to fix this)
I dont want to put you off completley, if budget is an issue then the ProNav does do the job for the price, i used mine for 2 months and it never put me wrong once.
My mate has one and he swears by it (he has never had any other device)
I now have a snooper s5000 truck mate but it is about £289.00
Hope this has helped