Bluetooth Gps Adapter Should I Get A GPS Adapter For My Phone Or A Stand-alone GPS Unit?

Should I get a GPS adapter for my phone or a stand-alone GPS Unit? - bluetooth gps adapter

I have a Cingular 3125 that a Bluetooth GPS could support. My budget is $ 250. I think I have to buy a Bluetooth device for $ 200 and the remainder to a map on the phone. Would it be better to just get a separate GPS device for $ 250? (For a portable automotive)