A few more choice quotes from the link;
"The C-133 had supported operations around the globe, and was even trusted with transporting Apollo command modules after they returned from the moon"
"They’d fly it again, if they had the chance. Among the group gathered at Delaware’s Dover Air Force Base, there’s a man for every crew station at the ready. They flew, maintained, navigated, and sometimes cursed one of the least understood aircraft in the history of the U.S. Air Force, the Douglas C-133 Cargomaster."
Reading the comments from those who know the airplane best are relevant as well