There is lots of kit out there. I just got my Denon MCX8000, which is just about the ultimate controller for at least mobile DJs. I would not touch the XDJ-RX for that purpose. I do still own my DDJ-RX which has done it’s job admirably, but was never 100% my choice (got it in a gear swap).
At the end of the day the only person who can determine what is right for you is you.
We advocate getting your (desired/intended) workflow clear first, which is seems you have done to some extent already. Next comes software. It needs to match your workflow (like the loop thing, although I am not quite sure what it is you mean there) as closely as possible. 100% match is pretty much utopia. Then budget (to prevent from being blown away by lights, knobs and faders and perhaps brand while not really being able to afford it). Finally shortlisting 2 or 3 controllers that fit workflow, software and budget and trying to get some hands-on time with them.
On a general note I can say that you might be reading too much into the whole RekordBox and club gear thing. “Traditional” gear is moving out of the booth, to be replaced by the expectation that more and more DJs bring in their own gear/controller. Picking software and hardware because you may end up in a club somewhere … I would stick with making my choices based on what is important to me, not what others may or may not do/have.
Also, many software let’s you use the CDJs in either midi or HID mode with it, giving you all you need in the booth. All you do is bring a laptop stand, your laptop and a few cables and you are off to the races. This is by no means an exclusive feature of RekordBox DJ.
Just my 2 cents as usual.
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