Sensible hat on...
I would say none of the above if you are planning doing a LARGE mileage. I personally would be going down the diesel route, something along the lines of a Seat Leon FR TDI or the other VAG equivalents.
Its all down to personal choice though. If I was travelling up and down the country on motorways and dual carriageways then the first thing I would be looking for is comfort, then fuel economy then performance. The newest diesels can do all three with the sacrifice of handling to a certain extent.
Sensible Hat off....
Go for the 330s, you know it makes sense!
Id be interested to see the responses of other forums on that particular group of cars...