Those wheels have been on my car for nearly a year now.
That black Axis just had Nismo suspension and wheels...
There are options such as air filter, oil filter, wheels, exhaust etc that are compatible throughout the range, but if you look at things like suspension (non-ARX), Speedo cluster (non-ARX) or the Nismo kit except the rear spoiler (non-ARX or Axis), alot will not work on an ARX in particular, and the Axis to a lesser degree.
I think what Iain was alluding to was that the Nismo M35 Stagea was only available in RS or RX form