OpAmps in Wah Circuits?

[varialbender]

A lot of people seem to take pride in not using opamps in wah circuits and sticking with transistors and inductors and such.
Is there really a big difference in sound quality? Using opamps looks more flexible, but is that at the sacrifice of better sound? Or is that just marketing mojo?

Thanks

PS thinking about breadboarding geofex's parametric eq and testing its wah-ability today