SOB Hill is an obsticle, not really a trail. It is a trail, you have to get to the hill somehow, but not any harder than upper swan, until you get to the hill. The hill is about a quarter mile long, tough as heck, but not that long. I think you can stand at the bottom of it and see the top. What it is, is a rock field with large boulders on it, on a steep hill. Without problems a capable rig should be able to go up it in less than an hour, down 15-20 minutes. This is assuming no straps or winching.
That's why you need the other trails as a part of the ride, to fill out the day.