Yes. The sites go quickly, like minutes. Don't forget that they become available at midnight Utah time. You can put down that you are on a multiday trip, but they figure that out anyway when a week or so later they send out the confirmation and payment info.
White Crack really stood out to me, really unique. I stayed the second night at Hardscabble B, but it was just so so, maybe because it was a cold morning and it is in the shade. The Murphy camps looked fun, but if you have a windy night it could be a tough one.
Take the time to do the Fort Bottom hike. Really interesting cabin and ancient ruin.
Enjoy.
