We live 1000' up on a windy hilltop in southern Scotland, so perhaps similar to your situation. Our tunnel is from Northern polytunnels which offers extra thick metal and diameter for the hoops, corner struts, end triangulation, crop bars and base rail - all to give extra stability in high winds. Ours has stood for about 15 years. The cover blew off in the early days but that was because we hadn't attached the battens the right way round. Since then all has been well. We check all the nuts and bolts before and after every big storm - initially they loosened off but now they seem to be more secure.
We put up a 2m windbreak fence around the whole veggie patch to protect the tunnel, but now after all these years the hedge we planted at the same time has grown thick and tall enough to take over for wind protection, so the windbreak can come down, on three sides at least.
I would also add - buy the biggest you can afford or have room for, as you will find plenty of other things you want to grow in it once it's up.
For ventilation (you need far more than you might think), we chose doors at both ends, plus a double width louvre at each end (in fact there are two one above the other, but opening the bottom one only happens when it's really hot, which is so rarely here that I wouldn't bother with that again). The only mesh we use is to cover the gaps for when the louvres are open to stop the chickens flying in, and over the doors when they are open. When it's very windy we keep everything shut, although others say to keep everything open - whatever, don't leave just one end open, and have proper doors with ground bolts, not just roll-up mesh.
If you want to grow salads in the winter, then mesh sides are not adequate, unless they are the sort where you can roll up the polythene when it's hot but have it down when it's cold. I don't know how that system would stand up to high winds, but Northern Polytunnels are happy to discuss your best options for the site. If you live somewhere without winter frosts then mesh sides would be great.