These shorts are cool. I'm 5'6" and approx 63kgs and I ordered the waist 31. They fit good enough and fall right on my knee ( not over or under )
But I'd recommend the Billabong Hatchet short instead, those are classics with a great fit, they look sleek and great for any occasion! if you do order those be sure to order 1 or even 2 sizes up , as the thigh area is a tad bit snug but nevertheless till look decent , not like those thight a$$ shorts that will soon phase out!