Define "slow". A 458 is SLOW compared to a LaFerrari. You have to define "slow" with a horsepower figure otherwise i can easily say than i prefer SLOW cars, like the a 458, R8, 911 etc.
Possibly a little common sense is needed. I think most people, although I am aware this is the internet, would understand what is meant by slow (ie. not a 458). And if you really want to be a pedant, power to weight ratios and aerodynamics come into play, not just horsepower!
It has already been said above, but for close fun racing, slow cars win hands down.