Layout and ergnomics of controllers is very important. It's not just about slapping everything on there, some thought has to be done to it.
Then again, there are so many controllers because there are so many preferences.
The VMS4 seems to have some nice spacing and light up knobs and buttons. I'd still prefer to have a light over it, but I'd want to see how this looks in a dark environment before I were to think about purchasing it.
If ADJ Audio is going to provide profiles and layouts for other software packages, that's awesome. This unit is of no use to me since I don't do DJ work, but regardless, a company coming out with that kind of statement, that's just not heard of too often anymore.
Now, excuse my ignorance on Serrato, I know someone using it for Mac. I don't know what interface he has, but I see no MIDI interface on it. I bet he's had it for a few years so it's probably an older interface. Not sure if Serrato is like Pro Tools, where it needs PROPER hardware to function(say, the interface for example). But I could certainly see if you have a MIDI interface, taking advantage of that. With MIDI IN and OUT, you can get dynamic feedback from your activity at the controller.