DR 250Z certainly are alot of fun, but a little gutless standard, where easly regestered in NZ which made them quite popular,myself and a mate race them our evo-lites class and after alot of work and a few failures we have them going much better.
They seem to shit ignitions but apart from that issue no major problems, maybe why I have 7 and only 3 with spark.
They turn up for sale often cheap as,if you want to make them go concentrate on compression and carb.