My friends in Italy have all confirmed the new Sky Window has not given any problem at all.
Also here on this forum you do not find anybody with a problem.
Somebody found the Sky Window not working properly, eg stuck in a position, but if you follow the procedure indicated in the manual you can deactivate the sensors which block the window if there is a foreign body in the mechanism. You can also reset the window.
This was not a fault but a safety feature in case a kid leaves its fingers between the blades.
The water, if any goes through, would only go into special tubes built directly underneath the blades and on the sides: all together this water is drained at the rear through an advanced and complex system which has been tested for years before adopting this window.
In the end ,even in the unfortunate case of the the window leaking, the water would not go into the car but in this special micro gutters.
I have tested the window under the most extreme rain, eg a couple of weeks ago there has been a small tornado here, and all worked perfectly.
If the electric motor would break, there is an emergency procedure for closing the window manually using a special tool which is hidden behind the Sky window control panel and this is all explained in the manual.
I would defintely go for it: I was very worrried before getting it myself but I have done my research, including Italy, where there are more Stilos than in the UK, and I would say 100% of people are happy with it.
Of course it can fail one day, but the system is built in such a way that you should not damage the car at all, unless the blades are broken by a vandal or something, then you would need to go to a dealer asap but then also the windscreen is a glass and could break if hit by somebody: this Skywindow is better than all previous sunroofs.
I have to admit a friend of mine has got a very old Fiat Tipo (if you still remember this car), he is in the UK, with the sunroof, after over 15 years this sunroof is still perfectkly working with no leaks: of course on forums mainly people with problems send messages, this is why you will always find more problems than "thank you" messages for Fiat.
Go for it.