I bought this as a small desktop keyboard for inserting simple synth lines into demo tracks and for that it does the job admirably. Obviously it takes a bit of getting used to as the keys are smaller, but it's surprisingly playable once you adjust. It's class-compliant so you don't need to install anything, just plug in and away you go.
The velocity sensitivity is a bit flaky I find - it does work, but it's tricky to control. The joystick is a novel alternative to the usual wheels - it has a small range of movement which means it's not as easy to use, but, as it can control two parameters at once you can do some cool effects with it that would be difficult to do with two wheels. The arpeggiator is a nice feature too.
The bundled software was a disappointment though. It's all severely stripped down versions basically, and not worth the needlessly complicated online process you have to go through to get it.