My 2003 350Z is starting to rust so it's time for a new car. Should I wait for the 370Z or buy a Cayman?

Road salt is the culprit, the wheel well rim is the location.

 

The new 350s I think are on par with the cayman and has enough support to easily overtake the porsche so in my opinion i would go for the Z, I could have picked a cayman myself and said, "Oh, I own a porsche" but I couldn't bring myself to the stupid and pricey maintenance if I ever got lazy for some reason, and If you screw something up on the Porsche you're paying a pretty penny to fix it.