I have a shinei fuzz wah which is an absolutely sick rare pedal built in the 60's by a Japanese company.
I've tried mixing a wah with Fuzz on my HD500 but it doesn't come close... this things like a wild animal with some out of control harmonics.
Everybody that hears it wants it.
Offer me the right amount of cash( so far I've been offered $1500) and I'd let you have it for modelling. Other than that I'd never part with it.