Ok I can see each of you guys points and they are valid.What do you think would be a upgrade to the current design??.

Oh with a case key on my key ring,most seals on heavy equipment are on cylinders sliding back and forth threw the seal.So there is no way a square seal would ever work in that application.But I do get the point of them holding up under high pressure.And in heavy equipment those o-rings and the surface area is substantial.I mean they are huge and thick.