Mine has very small valve cover seepage. IT has since the day I bought it brand new. I think all GT's with compsite valve covers have a small amount of seepage. Most people never notice it, but many I have talked to, do notice it.
It drips once in a while and you can smell oil burning. It drops right onto the exhaust pipe. The low point of the valve covers is in the back, so it drips there.
It equates to about a drip a week, so I don't worry about it. One time, as I pulled up to a gas station, it must have just dropped, because I could smell it. Then as I am tanking up, I see some smoke comming out from under the hood. Pretty lame considering the car has 5K miles on it.
I never took it in for warranty repair because I figure the hole front clip would need to be repainted by the time the dealership got the valve covers regasketed, and it would probably still leak after that.
Aluminum expands at a very different rate than plastic, and I am sure that contributes to the problem.