If you're heading to anywhere in the Southern area of France from Cherbourg, Caen, Le Havre. Try to make this part of your route.
Worth detouring for in my opinion. It's the first really nice road out of the ports I've come across. Stomps on anything I've ridden in Dorset/Hampshire) but there's better in the alps hence my conservative rating.
It's one of those that tempt you to turn round on and do it again (which we did).
Nice flowing route, through rural Normandy. Good corners.