Thanks for the 3 points. thstone; I think I will go with #1, the cheaper option

)
Bugger.
Truth is, I have a service history but it is not always official Porsche, and the car was clearly idle for at least 18 months whilst somebody had a problem with it about 5 years ago. The curious thing about it is she feels 'okay'. I know that sound dumb but I've just returned from a late night refuel and she wants to pull - almost as if I'm holding her back. I drive sensibly in urban traffic but I let her go on business runs on motorways and she feels 'right' when I enjoy it and shift at 4-5k, hitting the hot spot and suddenly we're topping a 120 and wanting more ... when I slow down.
It doesn't 'feel' like a serious issue so I'm hoping you're right with the cooler!
As I said, I'm not a 'petrol head' but I'm enjoying a car really for the first time (I was a motorcyclist).