I've had a Korum lightweight for a dozen years or so, and still going strong. Admittedly, I never put it up facing the wind (seems like a very daft idea), and just peg the back down. It's withstood some stormy weather. Sure, the vanes get pushed down during a very strong gust - however I would say that's expected behaviour.
It was even blown into the Dove a few years ago. I gave chase (on the bank) and when I reached the farthest navigable point a gust of wind miraculously blew it towards me on the bank. God, I love the Dove!