I do have airscarf, essential for resale 'cos everyone wants it. It isn't actually that good when the roof is down unless you have the side windows up, TBH I use it more when the roof is up and I get into the car on a cold morning, it still works when the roof is up although to a lesser extent.
Nice pics again, one thing your car is missing is bluetooth, it seems to have virtually everything else ticked on the options list, seems weird no? I've said it a few times recently, but silver really is the best colour for showing off the lines of the Z4, when it's clean and you see it in the flesh, it is brilliant.
What are you replacing it with?