Yes, I sparingly use wah for metal.
I also have the TWA Triskelion Harmonic Energizer that is in the video above.
I do not use it as a wah pedal but as a boost.
It is an MXR Q-Zone on steroids.
I have owned both pedals I feel comfortable making this statement.
Yeah, I'm a 40-year Zappa fan myself, and follow Dweezil, so I was very well aware of the Zappa connection.
That's actually why I was investigating it in the first place.
Andy's demo
totally took me by surprise and I hooked up an expression pedal to it the minute I got it on a board.
It just adds so much to it, I find it hard to imagine putting it in play w/o the expression pedal now.
I've never come across the Q-Zone before, which I find surprising, I'll look into that just for grins.
<Edited after watching a Q-Zone YT>
Ha! Yes, it's totally that, a Q-Zone on steroids, good to know.
I might get me one of those for another board.
I totally love experimenting with notched EQ curves in various ways, that's right up my alley.