After trying to get a set of Gas Struts to work on my hatch I gave up and went with the Manual ones from Austin,$10.76 ea they work great and as for the wind might pick the hatch up and cause it to close I plan on installing a strap along side the support to keep some downward pull on the hatch to keep it from lifting off the lock.
most of those manual props have a hole where they can be saftey locked in case of accidental failure due to wind or something else. If they don't you can drill a 1/4 inch hole and put a pin in it.