Hi Coolasluck - I believe the only sat nav models on the market capable of receiving digital TV (Freeview here) are the two Mio (formerly Navman) units -the V500 (5" screen) or the V735 with the mighty 7" screen. I have the V735 and in the van it doesn't look too big when dash mounted although in something like a Ford Ka or Peugeot 107 I imagine it would restrict the driving view a fair bit. Must admit I was disappointed when it couldn't locate a single channel in my area (Kent) but after some research I discovered Cornwal had already been upgraded for full digital TV, what the rest of the country will be going through in 2012, and when I tried the TV function on holiday there last week it tuned in around 37 stations and looked amazing! I was well pleased. Most of the ime I plan to use it as a sat nav of course but nice to know we can watch a bit of TV in the evening when in Cornwall again. Saying that though I did receive channels at Yeovil, Somerset so I guess it's safe to assume anywhere in the West Country will be good for some Freeview on these units, unless you're in a hole somewhere, lol!
GDog