What are you talking about? N95 (8GB) has got 100% free ***** maps, yes you have to pay to enable the voice tracking service, but surely you can do without the voice? And you can always install TomTom indeed, but you have a built in GPS receiver, so why the bluetooth one?
Never had such problems! Also be sure to enable assisted-GPS service, it will use your net-cell for much faster and preciser positioning.
I've heard the built in GPS is rubbish, I tried to get it working today on the way to the shop and it wouldn't connect... So I figure that is really is bad, a bluetooth GPS unit won't cost more than £25 and it'll mean I can use the N95 in the car, which is also why the voice would be useful =)