Glad to hear about the XDJ! Let us know how it is as lots of us are waiting for users to review them! I'm personally looking to replace my CDJ2000 with one.
I can't really help you with rotaries as I don't use them, but mrdorianjaames' suggestion is another great option as well.
Xone 92 is a very popular mixer, and you can throw a rotary kit onto that. Same with the DJM900. Although, I imagine if your father wanted a rotary mixer specifically, he is looking for one of the other kinds of mixers.
From what I've seen, the Rane 2016 is pretty suitable for everything.
My suggestion: do what mrdorianjames suggested. Has he considered going the standard DJM900 or Xone92? Or does he specifically want the isolators.
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