I've got a z32 and yes, have had issues in the past. Mostly related to age and heat - something that ALL internal combustion motors will suffer from. I've put a twin pass alloy radiator in and found that once on a spirited 40 degree day drive it was the Commodores and Supras running hot whereas the zed was sweet.
Heat related issues I've had include water hoses, Ignition module, radiator, heater core. I've had all my plugs changed as they were all rusted out when it was cleaned with a high pressure water hose when it was first imported.
Performance is great - top end it holds its own (300kph) and I've done a 12.7 down the quarter just with a zorst, boost, air filter and a tune.
In a nutshell, I wouldn't trade my z32 for a Line - unless it was a R34 GTR.
Good luck with the decision!