I have a work phone with 3.
I think they are terrible considering I can't get service in my house sometimes and I am in the middle of Adelaide suburbia, 15km from the CBD!
I didn't know GPS was free, cheers for that. I would probably go the offline route as I find the phone unreliable, $50 is pretty cheap and discounted prices from google cough may be even cheaper.
Good thread, lots of food for thought so far.