I bought this a while ago and have reserved judgement until I used it a few times.
When it is initially switched on it takes approx. 3 minutes to locate my position, the maps are really good, (the 2D view is a bit rubbish, 3D is far better), you have the ability to zoom in/out and roate the view 360 degrees, I have only lost signal a couple of times in areas of dense wood or when going through a valley but the signal re-locates you very quickly.
When you add up the cost of the individual parts provided (car cradle, map disc etc..) the price of the GPS works out to be approx. £60.00 which is a bit pricey.
You can download the European maps in addition to the GB and Ireland ones provided direct from the GO! website at a cost of approx. £20.00 when I last checked, but you'll need a big memory card (2gb minimum).
Overall It is excellent considering it's only an add on for a multimedia player.