I came through there in April on a CRF250L. A really nice ride. Mostly dry roads, the dirt part was a bit moist but enjoyable.
The army check point was trilled to se a Farang and I talked with them for a while. No Farang had passed for about two months, they said!
Strange because it is a really nice road to use from Nan and going south or going north.
The army guards where happy to see a Farang. They even woke up the boss so he could have a chat too. Nice people. After everybody had taken their pictures I was able to leave.
I had a lunch break in the middle of the woods to enjoy the silence. Just the sound of birds and some unseen animals.
The surface came in all kind of shades. Piles of cow dung indicated not much traffic on this nice road.