The tone options and the Q-knob bring a lot of choices when it comes to sound. Different outputs also bring a lot of versatility. In the combined mode, you can switch between the volume- and wah-modes with a press of a button (in this case bringing the footrest to the very top position). The other modes can be switched on/off with a similar motion.
Doesn't seem to drain the battery if left there unused, as it uses the input port as a power switch.
However, it's not flawless, as it suffers from the same problems as other wahs. The pots can be quite scratchy, even when the pedal is brand new. Luckily, it's easy to take the pot out for cleaning and greasing, although this one uses a modular concentric one instead of the ones you see on guitar knobs. Thus, there is less junk buildup but cleaning becomes harder. It's not impossible though.
Overall, nice pedal for the price, although one must get their philips driver and wd-40 ready if they think of getting this thing.