I bought this one, but when connecting it it turned out it was not compatible with my soundcard (RME Fireface 800). The problem was that since it does not use an external power adapter it relies on the power it gets from the midi jack. According to midi standard all midi outs should provide sufficient power, but in reality not everyone does.
If you consider buying it have a look here to make sure it's compatible with your hardware:
#Power
I would suggest adding some extra money and buy a proper one (like the kenton) instead. Saves you a lot of head ache.. :)