Crybaby Q-zone

Ok I've seen a few reviews about this pedal (and the MXR version) but haven't really seen what it does? I assume it's a wah tone w/o the expression of the wah pedal if that makes any sense? Saw a Slash set-up where his wah pedal chains right to the Q-Zone? Anybody ever use these and if so anything good to say?
# 1

Watched a couple of demos , seems to me that is gives you that quacky , nasal tone you get when you leave a wah pedal on in fixed in one position . you can set the tone parameters and sounds like it has a touch of overdrive . I just use the wah if I want that sort of sound , turn it on and leave it set to the tone I want , only takes a short sweep to hit the sweet spot . It's up to the individual , but I don't need another pedal in the chain to cover a sound that I use once a night.
# 2

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