I'll second smart1's post. I was up OAP to Langley last month, and there were several coming up from USL. It appeared steep in some sections, but none of those I talked to up there seemed to have any trouble. There was a big rock right about the junction that was a great spot to drop off extra gear and continue up to the summit for those that wished to do so.
After being inspired by some of those backpackers, the route down from that junction to USL is what I'm planning to take next summer as part of a trip, as a matter of fact!
