Just finished a 2 week driving trip through Scotland and after borrowing an Navman F20 from our B&B proprietor I decided that I had to get one. Bought one in Glasgow and drove all over scotland using the F20. Can't say enough good about it and its ease of use.
Now that I am home in the USA, I am looking for the US maps. Apparently they are out of stock. Have looked everywhere on the net to find the chip.
I too have a F20 and I love it. I have tried and compared the Tom Tom One against my F20 and I believe the F20 stands out by far, the Tom Tom actually navigated me 90Klm off course on one stage where the Navman F20 was spot on.