Your advice is requested.....

Having recently had the pleasure of driving into Central London at night, and getting horrendously lost. I have decided to invest in the TomTom GPS system for my O2 XDA. However I am becoming confused, as many of the GPS receivers state that they are water proof, does this mean that they have to mounted outside of your vehicle?

What I liked about the PDA solution, was that if you wanted it required no professional fitting as such. I was looking at getting the Arkon amplified power mount and the TomTom Navigator 3 software with GPS receiver, as far as the reviews state they should be compatible, but is anyone here using this setup, and are there any things not in the book I should be aware of before investing my hard earned cash?

On the face of it it looks like a good investment, which could save me time and patience. ANy hints and tips you may have will be appreciated.

TNT,
The receiver does not need to go outside the vehicle unless you have a heat reflective windscreen then you may need to do this. Otherwise most folk put it on their front dashboard.
If you go for the Arkon Mount that amplifies sound you will not be able to charge it and connect it to the Tomtom receiver at the same time. Your best bet is the Tomtom car kit which provides the mounting bracket and connecting lead which will charge both XDA and Receiver. The car kit is necessary otherwise the receiver will not power.
If you are worried about the sound quality, you could go for the Arkon Wireless Audio Adapter as shown here - http://www.totalpda.co.uk/Arkon-SF25...o-Adapter.aspx
Over all the above system is a good buy and very reliable, esp. in London, they even have incorporated the congestion zone!!