garmin for sure. I have the nuvi 240 which has everything you need (personally). It has text to speech technology and all the important things (POIs, etc.) without the unnecessarys such as an mp3 player. I play my ipod through a DC jack FM transmitter.

I bought a DC Jack (cigarette lighter) splitter which I wired under the driver side seat. The Garmin charger is plugged into that, runs under the driver side floor mat, up the side of the console (the section which is covered by the door when it is closed) and connects to the GPS unit in the top left of the windshielf. That way it is out of my main line of sight but easy to look at and access. Furthermore all you see is about a foot of chord running down the left (Driver-side) windshield pillar.

Considering I wasn't willing to put in a new head unit, or sacrifice dashboard space by using the credit card method some members have used (inserting a bent credit card in the slat above the middle AC vents) I think this is a pretty good solution.