It's fantastic. I'm running it on a Nokia 6600. Installation is a doddle and it has the very latest maps (The M6 Toll IS on it), and even though there is a smaller screen, it's very usable. The 3D map is excellent, as are the spoken directions. I used a Brodit Proclip & Mount to mount mine, which I thoroughly recommend. A much better solution than a PDA. The spoken directions mute when you have an incoming call! I also loaded the speed camera database from
www.pocketgps.co.uk on mine too! Therefore I only have to mount the phone in the MINI and not a phone, PDA and speed camera detector!
Let me know if you have specific questions. I can recommend the Forum on
www.pocketgps.co.uk for help on TTM.