We drove hiway 212 "The Warrior Trail" from Crow Agency, MT to Belle Fourch, SD in June.
The drive was typical 2 lane - good surface, with a couple of holdups for road work. They had / were resurfacing parts of the road - very smooth where the work was finished.
We stopped in Broadus for a rest stop - good park there to walk the pooch. Bought fuel at the station by the park - price was the best in town - but they made me pay for the ice for my cold drink mug! I guess when you have the show in a small town - you pay the price.
Anyway - plesant drive - would do again - don't plan on being in a hurry - pull off often to let traffic by - always some "speed balls" that back up behind you.
By the way - it was real green in June - probably a lot dryer now - and maybe not so scenic. It is mostly reservation - we had spent the night at Garyowen (7th Ranch RV Park) and toured the Custer Battleground the day before - very interesting.