I know there were a couple of defects, only for certain years..
Here's a link :
http://www.automotive.com/used-cars/recalls/11/nissan/350z/index.html
So those would be your cons. As far as performance, there is an extreme abundance for the Z. If you really want to consider on purchasing one, check out some forums and read what people whom have bought the car have to say everyday.
http://forums.nicoclub.com/zeroforum?id=168