I hunt 10 to 15 feet. In western SD 20 mph winds are the norm, anything below 15 mph we call calm. I always put my stands on the biggest tree possible to minimize rocking all over the place. IMHO, when the wind is up around 20, scent is not that big a deal, it is blowing all over the place so I don't think it benefits you to get higher. The deer are less likely to notice movement in the wind also as everything in the woods is shaking all over the place. I'm not a big fan of heights so 15 is as far as i'll go and I don't have trouble with scent or with movement.