The DJ2 is mainly targeted at users of the "Traktor" DJ software by Native Instruments. For that reason, it is not freely configurable but has some hardwired functions and sends fixed midi-values.
Anyway, it is still possible to use this controller with other (VJ)softwares, because in many softwares you can root incoming midi-signals freely to software controls.

Example:

I bought the hercules console both to test as a fun toy to practise DJ mixing and to see if I could get it to work as a VJ controller.
There's plenty of reviews of the DJ Console for it's audio capabilities so I'll just say that it works and it's fun.

As a VJ controller: it is actually a USB game controller but the latest windows drivers from Hercules make it emit midi signals for all sliders, knobs and wheels. There is no way to configure which controller number anything is it's all preset and it sends on midi channel 2, again I couldn't change that.