I just bought this keyboard and I'd like to warn about some points...
The height between Black keys and White keys is just 9mm from back and front end. On my piano, this height is 12mm from front end and 9mm from back end.
So this 3mm differences could make problems for some. I test another keystation and it was 9mm too. I'm not sure why m-audio decided to make different keyboard layout.
Yes I use "Kompas" to measure it. When I'm playing with it, I can feel the difference. The minus side is you can miss the black note while playing fast. However, you can play much more faster with the 3mm lower heigh of black notes. So, you can play faster but you should be more carefull
Maybe I'll get use to it soon. who knows