I had a run-in with the service chief at the dealership where I bought my 987, switched to another dealer, where I had phenomenal service. Then the service manager there was gone, replaced by the idiot at the first dealer, so I went back to the first dealer, and had fairly good help. BTW, the first dealership was where I had my Audi and BMW serviced, and I would give them both better marks than the Porsche guys.
But that is why you do a nationwide survey if you are JD Powers, I guess.