Upload & Sell: On
If 200-400L turns out to weigh as much as 600 II, I do not think that is someting I'd want to write about to my mother excitedly.
Obviously, 600 II is so much lighter than 600 I, however, 600 II is still one fairly heavy lens. Its length as well as a large girth add to the awkwardness of its hand-held use. Granted, 200-400L is significantly smaller, thus it should be easier to hold and swing.
Frankly, as a photographer, I'd have a hard time justifying 200-400L purchase. As a collector, well, sadly, that is a different matter.