Dunno about the HHR, but the few Cobalts I've been in haven't rattled or squeaked.
I really like my HHR, but on really cold days there are a few weird noises going on. It is made worse by the fact that the car is REALLY quiet (i.e. very little wind or road noise). There is a lot of added sound deadening on the HHR, so any little interior noise is going to be heard. That said, I was in a new Sante Fe that had way more rattles, and that is a far more expensive vehicle.
Back to the SS - I'm sure there are many of them on Autotrader for cheap - too bad that most of them will be either the 2.4L or Supercharged versions.
About the interiors - yes the Cobalt interiors are not as nice as the competition, but they aren't so bad that they will destroy the driving experience. Also, while the dash isn't as nice as the HHR's you are getting pretty sweet seats!
Still, if I were to get a performance vehicle I'd be getting the HHR SS. Just show me another small car that can go that fast, for that price, and still have room for the Border Collie behind the rear seat!
