Pioneer XDJ-RX or Numark NS7-II

They are indeed different beasts.

Not sure about the midi bit. I think you can use the RX as a midi-controller too, just need the mappings for your software of course.

There is a good live use report by Phil over on the blog now which is very comprehensive and should answer many of your questions.

We have some NS7 owners who will more than happy to chip in I believe, they all seem to love their vinyl platters.