Personally, and as stylish and fine-looking a feature as the Open Sky is, I definitely wouldn't go for it again. I bought mine "blind" (ie without actually seeing an Open Sky car in the flesh)
I'd avoid it again because:
a) £700 (+) is, on reflection, a hell of a lot to pay for what is really (in functional terms) just a big sunroof
b) although it claims to be an all-over glass roof, visibility through the rear section of the roof (for passengers etc) is very poor, and the rear "meshing" cannot be opened
c) it makes the interior like a greenhouse on hot days, and it seems ludicrous to have climate control AND a sunroof. Hot days are exactly the days when you want the sunroof open, but the car is so hot that you need the CC on!(rather like having your domestic heating on with the window open....)
d) most importantly, it prevents you from any carrying of luggage on the roof (roof bars etc). As a keen racing cyclist and canoeist who wasn't warned of the OS's inability to bear luggage, I'm pretty disappointed.
I'm utterly delighted with my A2 in every other respect, but the Open Sky has become a right nuisance. Be aware!
Crawfster
Amulet Red 1.4 TDI SE, Open Sky