I had already made that comparison on the old thread but the Swedes from Hamnen did not only the same, reached the same conclusion as they had made a fantastic video with both boats on the water. :-)
Before seeing the video some basic information about the boats:
The Arpege was on the origin of Dufour success as a brand. It was designed by Michel Dufour himself and built from 1966 to 1976. 1500 boats were made and that was just huge for that time and 10 years of production. It was incredibly modern for its time, featuring a deep bulbed keel.
Built as a cruiser son revealed that it was also a competitive racer and even today is far from a slow boat. The boat was light with only 3300 kg which 1200kg of ballast on a bulb with 1.62m of draft. It was narrow (3.00m), it had 9.14m of LOA but a LWL of only 6.71m. It had 35.5m2 of upwind sail area.
The Dufour 310GL is a great design from Umberto Felci, it weights 4940kg, it has 1300kg of ballast on a torpedo keel with a draft of 1.90m. Compared with the Arpege it is beamy (3.31m) but most of all has all beam brought back and a two rudder setup. The LOA is 9.67m (LH 9.35) and a much bigger waterline (8.70m). It has 50.3m2 of upwind sail area.
Two very different designs, both great to their own epoch. As all modern boats regarding their older comparable models the Dufour 310GL has an overall better performance and an incomparably bigger interior volume.
Regarding the performance the two conditions were the Arpege would have a closer performance would be in very light wind or close upwind. On the video, besides being able to see the differences between the two interiors we can see the comparative performance close upwind with medium light wind, with the 310 being faster.
A pity they had not showed the comparative performance on other points of sail where the 310 would be much faster.
The video, as usually is very funny and as I don't understand Swede I can only see what was going on. If someone understands Swede I would be grateful for one or two meaningful comments regarding what was said.