Possibly the most annoying thing is that it has absolutly no user preferences that work. having been a driver for so many years when I travel I like to avoid the motorways, but the navman will only select motorway routes, if you use the adjustment and select "less" motorways it makes no difference it will still direct you to the motorway. If you select the motorway junction as an avoid area (you can't actually select the motorway itself) it will just direct you to the next junction.
Buy a TomTom.

I am a taxi driver, and I am a heavy user of satellite navigation.

I have had the Navman iCN530 for a few weeks, and I am having problems with this model all the time. Navman can repair the unit, but they would not provide me with a replacement during the repair, so I have had to buy a new GPS unit to have my ICN 530 fixed. I will try the TOM TOM ONE V 2.

I tried this Navman iCN530 satellite navigation system over a 30 day period every day all day up and down the country - it's a nice, compact, well thought out design with good graphics and a nice user interface. It's quick to operate and it has a couple of nice useful features that I did like BUT it did send me wrong a few times and once sent me to a pub when I really needed a petrol station (although I suppose the pub was a good second option!) so it nearly got thrown out of the window a couple of times by my boss because of the routing issue. I eventually took it back and exchanged it for a Tom Tom 510 which for me is the better system - see my other review.

The Navman iCN530 unit is small with a large screen, very easy to use and able to use straight from the box. There are plenty of options and you can add your own points of interest. Be wary of updating as it managed to delete the voice files. Always make a backup first! A quick call to the Navman support team and all went ok.