I wore Magnums on the floor for a few years. They didn't hold up as well as the RW's, but were much lighter (and cheaper).
http://us.magnumboots.com/?gclid=CMe2vsDilrsCFTNp7AodlWoAUwMy local Army/Navy store carries them and I'll probably pick up another pair this summer. The mesh is great on hot days.