We use our old 1956 f-cub a lot cutting the food plots in the woods, and it cuts some pretty thick tall clovers and alfalfa. We use to have one on the farm back in the 60's and 70's that I cut the pastures with and the ditch along the hwy.
Both are/were the 60" belly mowers and they performed their jobs well.
I can guarantee my 1872 isn't going to work all that well in the same situations. As the f-cub isn't going to do well where the 1872 shines mowing the lawn around the home stead either.
So rather than comparing the two, just have both to cover the chores that need to be done...