In my experience the best tub for poor roads are Continental competition, they are very resistant to punctures, but quite heavy and roll very slow. Tufo are far better for racing. Their 215grams s3 lite is quite good for road races and the 195 grams are also good but for special occasions, as the rubber compound is very thin and will not last long. This is why conti's go so slow. Lots of rubber compound. Dugast would probably not be good for bad roads due to the fact that they are aimed at being race day tyres and at the price I would probably not even go down to the shops with them
When you search you can buy the Dugasts for 55 euro.
They are quite good for poor roads. Museeuw uses them at Paris-Roubaix (26mm)