@whart I have the latest Nord 5. Like anthing it does some emulation better than others. If you go to the online library you can fine tune. For Rhodes emulation I prefer the Korg SV-1. The Korg SV-1 doesnt do piano as well as the Nord but it does Rhodes well and it has a weighted keyboard for a better piano like playing feel (my Nord is best suited to Organ with its waterfall keyboard) and organ drawbars)
I plug the Korg SV-1 midi out into the Nord and the Nord produces the piano emulation, mellotron, farfisa and other sounds I need. The Korg does a great Oberheim too.
In the end I settled on these two keyboards for the majority of needs. The split function allows me to use both keyboards sumultaneously for different instruments. Neither the Korg nor the Nord do everything well but together it is like Jack Spratt and his wife - got most everything covered to a very high level of authenticity. Short of buying and servicing all the original instruments - i would need a dozen or more keyboards - I find this solution superb.
I am not sure what Nord you have tried but there has been significant improvements over the years. Also the speakers you choose to connect to tbe keyboard are critical - Genelec 8020 are very good for the nearfield sound of the listener while a keyboard amp is necessary to achieve high volumes in a band setting where you compete against drums and guitar.
This is Benmount Tench setup
http://fohonline.com/images/stories/16/07/current-foh/mudcrutch/tech-miking-shots/MUDCRUTCH%20BENMON...