Originally Posted by NormanF

25 C is a road bike tire width and 35 c is a commuting bike tire width. 35 c is better suited to riding rough roads and carrying loads.

If you want to add fenders on the Gaston, you may have to size down to 32 C to get them to fit. SKS and Planet Bike make high quality plastic fenders. As far as rear racks go, Old Man Mountain is reasonably priced and durable.

For panniers, I have 40 L Basil Cote D'Azur panniers from a respected Dutch manufacturer. Plenty generous enough to haul home a month's worth of groceries from the store in two round trips.