If you're in a big rig, don't even bother. We have a 40ft combo with only a 23ft TT and did not even attempt to back into one of the few spots that looked as if it *might* accomodate our set up. Instead, since it was off season, we parked in one of the parking lots. It worked out fine and the rangers didn't hassle us or anything, but it was less than ideal. That said, this state park is not to be missed if you're in the area, simply because of the cool geologic wonders of the sinks and the rise. Maybe visit the park as a day trip from one of Lander's other RV parks!
Great value for the $34 we paid with the Good Sam discount. Clean, lovely lawns and green space, friendly staff, etc. Just an overall nice place to stop if in Missoula. It is about 10 miles from the city center, but it is a quick on and off from I-90 and it isn't like there is a better option closer to downtown. Gravel sites seem mostly level, though it takes some eyeballing and readjustment to find the sweet spot--the only reason I'm not giving this place a 10.
For a dry camping state park, this was an excellent campground. The main draw, the ghost town of Bannack is an absolute treasure. You could walk around for hours exploring the abandoned buildings all over this town. The visitor center is a wealth of information and great reading material about the pioneer/gold rush days in early Montana Territory history. This is the perfect overnight stop if you find yourself wanting to cut the drive from Idaho Falls to Missoula in half. Keep in mind that the campground is really there to be a base to explore the park, but there are some BLM areas adjacent to the park with hiking trails if that's your interest. Seriously, if you're at all into old west history, this stop is a must!
The owners/managers of the park are really lovely. They really go out of their way to make you feel welcome and match you to a spot that's good for your needs. Although the sites are gravel, ours was perfectly level so we had no issues. Further, even though some of the amenities are older, they work just fine. We did 4 loads of laundry and everything turned out well. We stayed two nights because the weather in Idaho and Montana drove us out of the mountains (as well as did the government shutdown), but we were glad to stay! Would stay here again.