not used proper race boots, but i had a pair of proper thin soled classics gone to a thinker soled pair and i can't drive on the limit as much and feel quite clumsy on the pedals, i have size 12's so really need to be on the ball cos most cars i can catch more than 1 pedal by accident .

i would say they are a good investment but you'd have to get used to them at first cos it'll feel weird if your not used to having a lot of feel through your feet.