My Nokia 3660 works fine when I'm in one place but anytime I'm driving it seems the handoff from tower to tower causes the call to be dropped despite a full signal.

Is this a network issue / a phone issue / or just bad luck? I'm looking for a new phone so if this is a Nokia issue it would make the next phone choice a bit easier... 6820 (maybe the 6822!) / Blackberry / A630