THE ONLY DIFFERENCE I CAN FIND SO FAR IS THAT THE DAWN ROSE IS DONE IN A COUPE SHAPE FOR THE BOWLS. I AM LOOKING FOR THE SAME ANSWER.
P.S. THE SWEETHEART ROSE IS SOMETIMES REFERED TO AS WHITE ROSE.
Additional Information: The Dawn rose is a flat plate and the Sweetheart rose has got a brim on the dinner plate. (I don't know what that's called the way it is). The difference may only be on the plates.
Sweetheart rose pattern has gold trim