Did the dealer offer 24 hour test drives as an option?
Eventually... problem is i guess they get lots of people going in there asking for test drives just to hoon around in a car they cant afford, so they have to think you are serious before lending you a car for a day really (have a mate who changes his car every year pretty much, and he has 911's, s3's etc for weekends all the time cos they know he will buy one if he likes it).
I did the old "well my wife really needs to drive it and see how it does on typical daily use" kinda line... but they didnt fight too hard. We had already discussed price, how im paying etc so they knew as best they could I was really interested. I would say if you are really serious then say you cant make a decision without having one for an extended test drive, see what they say. You can always try another dealer if they dont play ball.
I had some new toys appear last night, fan washer jets, wheel covers/bags (for my summer/winter swop over) and a huge amount of overpriced cleaning/protecting stuff... just need the car to slap it all on now. Oh, and should also be getting my winter wheels/tyres today or monday