Slow so far. I've backed off this past week because of sickness and general business, but overall I would say that the plan I made is too ambitious to begin with. I'm going to ruck only twice per week for at least a month before I up the volume on that.
I'm in Arlington, VA so there's nothing I can do about the elevation. Although I will run as much of the course as I can and will (duh) finish as quickly as I can, I'm not really competing, so I'm not going to let elevation worry me. There is a good amount of elevation gain, however, so I think once January rolls around I will add in a third session which will be hill or stair walks with the ruck.
Bottom line is that I am 200lbs and walking with 35lbs is really nothing to me (at least within 15 miles or so). Running with it is a whole nother animal. I am finding that in the initial training, I am trying to run way faster than I should and crapping out after a few minutes. Twelve minute miles are just fine with the ruck, but I'm totally accustomed to the pace.
Sort of rambling, but you get the point.