Diesel --- front engine -vs- rear engine

A friend of mine owns a Winnebago Journey D.P. (rear engine) and he had to add insulation over the engine compartment because the engine noise was so loud he couldn't sleep back there when his wife was driving! I owned Harley Davidsons all my life and I'm grateful for Honda and the Goldwing because, Honda motorcycle technology has forced Harley to build better bikes IMHO!