watching how someone drives seems to be a fairly good indicator of their temperament, their disposition. specifically how they negotiate an extended consistent radius turn; i.e. a cloverleaf exit [i did say specifically.] underestimating entry speed, sawing back and forth, on and off the accelerator or brake, lack of smooth inputs should be flags.
as annoying as eating on a first date can be it probably isn't a bad idea as it provides useful information. i think driving should be involved though. go karts seem appropriate.