I've been in mine through 50mph gusts with no ill effects, though it was little noisy like mentioned above. It definitely helps if you're able to park either facing towards, or away from the wind instead of broadside.
Also, like stated above, I've had one instance of driving with the top up. On the first big trip we used ours on, I forgot to latch the top. At around 70mph, all of a sudden I felt the truck slow down as if I was hitting the breaks hard and got a lot noisier. I realized very quickly what had happened. The front opened up, but not the back, and there is no evidence of any issues, and looked over EVERYTHING on the front end very carefully.
Don
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