I've used Garmin and TomTom all over UK and mainland Europe - never got lost or 'stuck' but have certainly been led through some very torturous routes ! So always proceeded with caution ! Then bought a 'Snooper' dedicated Camper van and Caravan Sat Nav, with the ability to programme dimensions and weight of my Eriba - this I have found to be a blessing and far better :) However I now have a car with built in Sat Nav with only the ability to choose route types,ie fastest, shortest and avoiding things like unmade roads or M Ways etc ! Not had any problem so far whilst NOT towing, but feel very inclined to use the 'towing programmed 'Snooper' when pulling the Eriba ! ! :) :)

I think one of the advantages of Sat Navs that hasn't been mentioned is the 'last 2 miles' effect. Even as a single traveller (my partner lives in the US and I often 'pre-position' the van somewhere in Europe and then pick her up at the nearest airport) with a bit of pre-planning and working out your chosen route (ie, the major way points - road numbers, towns etc) it's the last few miles where you leave the major roads and head towards your chosen campsite that gives the problem solved by a sat nav. At that point, they are a boon. I also pre-load the sat nav with exact spots for camp site entrances by 'downloading' them from maps on the Tomtom web site. I'm on my second Tomtom, a 'Go 5100'. I like it a lot. It has world maps that have lifetime (sic) update. I can preload destinations, as I described. I can even preload routes that I plan on their web site and it has voice control which saves me furiously prodding it with my finger when I should be concentrating on my driving. But like much of this sort of technology, you probably love the first system you use and never quite manage to adapt to other approaches offered by other manufacturers.

But that's why I suggested my approach of locating the camp site entrance on an internet map (easy to do on Google maps in Earth view) then using that location to download to my Tomtom from the equivalent point on the Tomtom provided internet maps.. Works for me, anyway...

But you are right, some 'addresses' don't actually give you an accurate sat nav location..

I bought a second hand Snooper sat nav, as our car then and now did not have fitted sat nav, for use when towing. Wife always has map on knee but touch wood both have agreed on routes when towing.

I certainly wouldn't claim to be an expert when it comes to using GPS devices although having used them extensively mounted on motorcycles and cars over the years it might be fair to say that I have had plenty of experience is using them and in particular planning and following routes that I would wish to follow and not what Herr Garmin thinks I should be following.

For starters - most if not all GPS devices have the allowable road speed limits programmed into their algorithms. So if the end user is positioned at point A and sets a destination of point B the device will work out the quickest route based on all applicable allowable speed limits. This doesn't take into consideration pedestrian crossings or having a slow moving HGV in front of course but can mean the device cutting off corners if it has calculated that the allowable speed limit through the housing estate is quicker in time than taking the outer ring road for instance. This is where zooming out a bit can often help to give a larger overview of the land layout where it might then become obvious that continuing on the outer ring road might be the better option and thus overriding the instructions of the GPS.

I think it's fair to say that when towing the caravan most of us have had a look at a paper map and have a general idea of the route we want ideally to be taking before setting off and in most cases the route is confined to motorways or main trunk roads. However, for one reason or another, it might be the case that the user wants to travel down a certain route which, from experience, might be more picturesque for example in which case simply setting an end destination of point B and hoping for the best is certainly not the way to go.

For more accurate route planning to ensure that the roads travelled are actually what is intended and to avoid the odd cutting off of a corner which might well be good when driving solo but not with the caravan behind, I would recommend digging more into the GPS menu prior to leaving home. Most modern Garmin devices have a menu entitled 'Apps' and from within a sub-menu entitled 'Route Planning' which is a much better option than simply entering a final destination (point B) and pressing 'Go'.

During the planning stage of last years trip which was 1150km east to west from our home in Germany to the French Atlantic coast I centered my plan/route around refueling and break stops. To this end I used Google Earth and noted the GPS co-ordinates for the stations that I either intended to stop at for whatever reason. My GPS device also contains fuel stations etc but I found this method better because Google Earth offered a wider view of the land mass. Once I had a set number of co-ordinates I then entered these into the device using the 'Route Planning' menu option. Having a wider view of the land mass in Google Earth I was able to determine any possible shortcuts that the GPS device might take and where necessary added additional co-ordinates (termed Waypoints in GPS talk) to force the device to remain on the chosen route.

If this all sounds like hard work one should keep in mind that more often than not we have booked our end destination many months beforehand and so have all the time in the world for careful route planning. The 'Route Planning' menu also comes into it's own when touring where instead of adding the co-ordinates of fuel station one enters the touring stops.

Where the 'Route Planning' menu really comes into it's own is on those occasions where the Campsite has stipulated a particular route that visitors should take to avoid particular sections of road for whatever reason. In this case, the co-ordinates of junctions on the stipulated route should be noted and entered as part of the Route Planning thereby ensuring that the device follows the stipulated route and not the more obvious one which the Campsite owner would wish you to avoid.

Good post Deeps.
An example from this weekend.....we were routed by the fastest route option from here to East Mersea. It was a picturesque but rather narrow and twisty country B road for part of the way. It included 6' 6" max width bridge. I know we can negotiate these with the caravan behind flicking the car mirrors in (because the towing mirrors make us wider) and we did this successfully. However parts of the route could have been awkward if we had met a wider vehicle. Whilst at the campsite i used the route planning option in the TomTom to set way points for the return journey to force the route planning onto more suitable roads.
TonyP