I liked it very much, it was a lot like described. Nice curves, especially along the fjord. That part is the best! The tarmac is not that great in many places, but good enough. The cars were not such a great issue but these cyclists.... Instead of riding in a column they often prefer the row and occupying the whole lane instead so watch out!
Great curvy road passing through some very nice, tiny places by the Drammensfjord/Oslofjord (Holmsbu, Sæthre etc). Could be quite packed by cars in the weekends making all the nice curves less fun. On a great sunny summer day without too much traffic it is a superb choice for a ride near Oslo.