The RV22 from Lillestrøm/Fetsund all the way to Mysen-Rakkestad is about 60km and more. It has some really great views, lots of good corners and some nice straight strips where you can pick up some speed without cameras and cops that bother you. If the weather is nice and the traffik is low (drove it 2X and traffik was very low) you have 50km of fun waiting for you.
This is the perfect route for those who travel South / North (or vice versa)
and wish to avoid Oslo.
The route is much more pleasant and interesting than the E6 which the vast majority use.
The difference in time-comsuption is almost non-existant (unless you use the E6 straights to speed).