Hi There Chappy,
Its an interesting topic you bring up. I have a 147 due to arrive soon with the CONNECT Nav+ System. As I am importing from Denmark mine does not come with the Navigation CD, I have to buy the CD from a uk dealer for £147 (Ironically).
I have heard that there is a annual subscription fee for the CONNECT part, but I don't know how much, neither for the suscription nor the calls it makes.
The phone part of the system is a Dual Band GSM phone, so it will work with any UK Celluar Company. You simply plug in your sim card, although it has to be the credit card size, but I am told that the car comes with 2 holders.
I know Gronk has this system up and working maybe he can give his comments.
As for your earlier post, you may want to look at importing one personally. I bought a car with ALL the extras (as you can see from the signature!) and it cost me more than £1k less than the stardard UK price without extras! Send me a private message, if you want some help.