This is my 2 cent that I posted on the touring forum when OP asked about 35 mm tires.
'Another thought-- Depending on what type of touring you are going to do, your weight, and the amount of gear you'll have; 35's might be overkill. We have done several long tours, incuding a fully loaded trip across the US on 28mm Continental Ultra Gatorskins. They are light fast and durable. I changed my wife's and my bike over to 32 mm Schwalbe Marathons this fall, and plan on taking them off before our tour this summer. Both my wife and I agree that they are significntly slower, and the difference can be felt on the hills. I'd really like to try the Conti's in 32mm, but can't find any in that size'.
We have not had any problems running 28mm on our touring rims (24mm width).