There were two versions of the Nur availible
V-Spec II Nur - Build on your standard run of the mill V-Spec II. Extras included N1 engine (24U block, rods, pistons, oil pump, water pump), N1 turbos, gold build plate and availible in all colours, with one extra limited to the Nur which was Millenium Jade (JW0). It also had the carbon fibre hood with NACA duct.
M-Spec Nur - Build on your standard run of the mill M-Spec. Extras included N1 engine (24U block, rods, pistons, oil pump, water pump), N1 turbos, gold build plate and availible in all colours, with one extra limited to the Nur which was Millenium Jade (JW0). It had the standard aluminium bonnet found on all series I GTR's, and series II M-Spec and non V-Spec II's.
The difference between an N1 and Nur is, the N1 has removed rear wiper, removed abs, removed air conditioning, removed radio, removed sound deadening.
The difference between the V-Spec II Nur and M-Spec Nur are, the M-Spec has softer "ripple control" suspension which dynamically adjusts dampening to provide a comfortable ride and leather seats. It also doesnt have the carbon fibre undertrays the V-Spec II has.
So, in short, they are basically an N1 with your daily driving creature comforts (and the very last of the Nissan R34 GTR's ever built, so they are holding their prices very well).
I have seen 2 genuine Nur's in real life, both a V-Spec II and M-Spec. Very nice cars, but asthetically theres not much different from your normal GTR (aside from the Millenium Jade paint and gold build plate).