Ibought a Nav Man F20 just over a year ago for my new job, its basic, got no europe maps, just britain. and its the best bit of kit i own. They don't make the f20 now, it was replaced by the s30 i think, poeple in the same job swear by the NavMan
I bought a Garmin sat nav a couple of years ago - much cheaper than TomTom and the nuvi had a lovely big screen that I could see properly... as well as being really easy to use. The only trouble with all of the satnavs is that you have to buy new maps on a regular basis as more housing estates/roads/etc etc get built so you need to take those costs into account when choosing one. When I was first looking at Satnavs, I really liked the look and build quality of the Sony but it was exceedingly difficult to use compared to the Garmin.
Last weekend a mate and I were travelling through mid wales and we got totally misdirected down little narrow lanes by her TomTom... it told us we had arrived at our destination when we were in the middle of nowhere ! I ended up buying a (paper) road atlas from a petrol station and regretted leaving my Garmin at home on the dining table !