I've reviewed both the iTrip and the belkin FM thingy and both are good but in urban areas there is a lot of breakthrough from local stations (FM is so crowded in London).
www.lordpercy.com/belkin_tunecast.htm
I would go for a hardwire if at all possible.
And Cyril thats one nice setup, i though i had a lot of gadgets in the car...lol anyhow the TomTom GO unit is going in soon so that'll be another screen!
LP