Great build quality
Probably the best single function expression pedal you can buy. I have a Behringer pedal that can more easily control two paramaters and has a wider axis, but these seem to be more precise and definitely have a better feel and stay within the optimal boundaries of most expressive-modulation paramaters. And, undoubtedly, they work better than anything else I've used for Moog keyboards, and arguably all other analog keyboards I've used. Since it can only easily control one function, it can be useful to buy more than one... other than that, this pedal is basically perfect.