You also have to consider whether you run 23 tires or 25's. You know, more pros are running on 25's now, but not all. The 25's might be more aero when used with a wide/deep rim. Of course, if you're using a wide/deep rim you could have trouble in the wind at Gila. That might mean a narrow/shallow rim, which would mean a 23. Except there are some rough sections of road, and the 25 might reduce the chance of pinch flats. The 25 is also good for reducing vibration, which could make you fresher at the end of the race or in later stages, but the 23 would probably be more aero on a box rim, which might keep you fresher itself. You've got a lot of very difficult decisions ahead of you.