The route starts very nice with the corners of the Lierbakkene.
Then you go South along the Drammen fjord, for superp scenery and very good corners. The inland-section does have some moose wandering about - dont hit them as they will do lots of damage!
If you want a little detour for lunch, go down to Holmsbu hotel. They have a good (white-tablecloth-)restaurant and a spa.
The route will naturally go together with doing the route up along the Oslo fjord (R281).