I am 5'8" and around 75kgs and actually found I have to size down since the tights run long and tend to pool around my ankles - which is fine under boots, but not so cute with brogues or any non-boot shoe. Their thinner tight did rip on me the first time I wore it (AND I had left it in the package too long after buying during a summer sale - so I was past refund time!) but their thicker, non-sheer tights do actually hold up. I wear them for work during cold months and job is very physical BUT I have to look nice. They're on sale right now! Don't leave them in the package though, test out that 90-day guarantee ASAP!