Do those Dunlop wahs still have a tone/volume pot? If so, that's what got me to stop using my ol' GCB95, and my Jimi Wah. I was tired of buying new pots when the old one got scratchy.
I'm not sure what sonic quality my Boss V-Wah is, but it's good enough for who it's for (bunch of drunks screaming Freebird), and there's no pot in there, so it never wears out. I can dial up a wah model (yes, it's kinda a little modeler and it's all digital) and adjust the wah range (usually very low - this thing has too much range) and I'm good. The one thing that got me about this wah, besides not needing to replace the pots, was the lower end range - very Satriani-esque. That's all I wanted
It's also got a boost (in the heel button) which is ideal for clean patches, not so for dirty ones.
One other added benefit: it's lightweight, great for a pedal board
Some rack wahs I've heard sound amazing, but for the money and convenience, this little pedal gives me several wahs to choose from on the fly. Also keep in mind, I use my wah primarily on clean funk tones (like some Bruno Mars, Michael Jackson, Prince's I Wanna Be Your Lover), only a couple heavily driven tones, like the solo in Let's Go Crazy by Prince. YMMV