The Madone is a Kenyan runner. Lean and nimble, built for speed, weighing not a gram more than it should. The carbon frame absorbs road shock like a marathoner and it could outrun a cheetah.
Whereas the beach cruiser's squatty, elongated, all-steel frame is sort of built like your Aunt Mabel from Kansas--old fashioned & heavy, and those bulbous tires ensure the ride is equally bouncy.