I needed a simple foot controller for multi-effects. My two main concerns were price and size and this pedal meets both.
It is plastic, so it may be not as durable or road-ready under heavy use, but for home or studio, it is perfect.
I've used a big boss FV and also a typical mission engineering and besides the construction, I didn't feel any difference when doing wah-wah effect or volume swells. Also, compared to those pedals, this is much lighter (probably because of the construction).
For the price, you could no go wrong with this pedal for expression on multi-effects. I have not used it directly as a volume pedal, so I can not comment on that.