"I've got a copy of his Military History of the Western World. He's highly opinionated, but very readable and very interesting."
I also. His "The Generalship of U.S. Grant" I also like. It destroys the myth of Grant being incompetent. Well, except that most don't give a fig for the truth if they don't like what they see.
I think Grant was a pretty darn good General, especially compared with his predecessors at the Army of the Potomac.