I was not impressed with the way OZ designed their economy cabins on the upper deck - I felt too confined, and could not move around the plane easily because of this. Because of the long flights, I like to walk around and get some exercise, and this is why I think I'd like the main deck better. It did not feel like a large plane upstairs. This flight from ICN to LAX had some terrible turbulence over Japan (thought the whale wouldn't be so bumpy!)