I had a mkI till 6 months ago and the sole reason to sell the car was the "abomination" hood. It leaked in so many places that I just had enough.
I can't comment on the S1 as my car is an S2 and I am led to believe the hood is a big improvement. My comments stand for S2 onwards.
Just on the ferry back from St Tropez (via Calais of course) where we were subjected to the odd shower and where it poured overnight every night. No problems again. I also managed to get the roof closed (utilizing the help of my passenger while still moving at 20 - 30 mph
