Since weight came up.. I weigh about 195 when in good form and have hit 220 when not.

When I rode the Trans America I ranged from something like 210 to 190 over the course of the trip. I was carrying between 40 and 50 pounds over the course of the trip. 32mm tires were fine for that and I never wished for wider.

On my other tours I weighed in the same range. I carried less gear though (30-ish pounds). On those tours I was very happy with the 28mm ultragatorskins and think they would have been fine on the Trans America trip as well.