woozzle

hi. im on the lookout for a uk gt coupe. just taken a deposit on my 3.0 z4 so hoping to purchase soon. today i test drove a 04 coupe 77k very nice condition, but as i whent around a roundabout the back end stepped out and me having to give a bit of opisite lock to correct....eat your heart out stig. anyhow the wife was not best pleased and i nearly crapped myself to be honest. pulled over switched the esp botton on and off so it displayed the icon on the clocks so seemed ok. so pulled away quickly to try and spin the rear wheels with the esp on and the traction icon showed up and controlled the wheel spin. so is it possible to get in the car start it up and drive away without the esp being on or could it be a faulty esp??? thanks