MFD 2 bar boost limit is the nismo edition which also has increased temp limits, lap time info, g-force lateral meter and able to data log too. These are missing from the nur's unless someone has upgraded it.
Overall, 34 GTR nur's don't have any problems unless you track one and then you should upgrade the N1 oil pump, add oil cooler and oil catch can with return line to sump (not needed though).
Just make sure owner uses top quality oil considering there's diff oil, getrag gearbox oil, engine oil. I use Redline range for all my oils.
Read this excellent guide from a while ago - http://theclippingpoint.blogspot.com/2007/12/buying-gt-r.html