Yes, as I have written earlier I went from a Beneteau Oceanis 40 2007 (new) to a Dehler 43 CWS from 1993 and then 2011 (new) to the current Wauqiez Opium 39. The Dehler 43 CWS is rather similar to the 39 CWS.
I have very mixed experiences from sailing these and other boats before. The Oceanis was overall rather nice but too beamy aft and too little ballast for a single rudder set up.
The Dehler was a very "traditional" performance cruiser with big ballast, rather narrow aft parts and a high rig with good hardware. All this resulted in very high loads on everything but apart from that a very nice boat. We sailed it home from Fehmarn in Germany to Gothenbourg in 32 hours with an avarage speed of 9 knots and that included 6 hours of motoring in the night doing only 6 knots. During the last 6 hours we had 46 knots TWS dead from behind and we had only one reef in the big main and poled out jib doing 11-13 knots all the time. In these conditions the boat was surprisingly stable, probably due to the high speed but compared with the Opium the biggest advantage for the Dehler is in very light winds where the Dehler has a better release aft and less wet surface.
On a beat I find them pretty similar and in more normal downwind sailing wind speed the Opium has a higher average speed and as you said, less rolling. It is nothing you reflect that much over initially but after a while you start noticing
that everybody is relaxing and behaving as if we would be sailing in sheltered waters with a tws of perhaps 12-14 knots when it is in fact big swell and blowing 20-24 knots. And "stressing" the gennaker with the aft beam and double rudders is less of a problem compared with the earlier boats.
What we initially noted most is the so much lower loads on everything. As you discussed recently regarding hoisting the main with electrical winches, on the Dehler that was definitively a must and the 12mm dyneema haylard was only 6 mm during the last meter. On the Opium, with 2:1 set up my wife easily hoist the smaller but still significant main all the way by hand, only winching the last 20 cm. Low weight demanding lighter gear giving lower weight....
Still, the Dehler was a very nice boat and we mainly sold it due to finding it too big. But the joy of speeding along with the light Opium riding on the aft quarter is nothing you could experience very easily on the Dehler.
Regarding Erics recent note about boom wang I totally agree. On the Opium we mainly use the rather wide traweller for trimming the main and it is a feature I definitively would not be without on a boat. Sailing upwind it is better to switch to small jib on the inner forestay and keep the full main somewhat down the traveller, than keeping 105% genua and reefing main.
Regarding the X6 and comparison with oceanis 38 the X6 also has double rudders,
Thanks for the very informative post. It is very nice to have you and Eric aboard this thread. Regardinf the Hull of the Dehler 39 CWS and 43 CWS even if both are relatively narrow by modern standards, as you can see, they are quite different being the one from the 39 much more influenced by the IOR rule and the 43 a much modern one. Modern means not necessarily beamy
I bet that difference has a significant influence in what regards rolling and downwind sailing.
As you and Eric pointed out a well designed boat based on solo racers (beamy and with all the beam brought back) rolls less and give a more easy downwind ride, following seas or not.
That does not mean that a well balanced and designed narrow boat is necessarily a roller and cause difficulties, or needs a full crew to control it going fast downwind. We can see that this narrow Luffe 40.04 goes nicely and fast downwind on autopilot with a remarkable directional stability:
It is just that on one of those light cruising boast derived from solo racers you can fly a lot more sail without losing directional stability and that allows even more speed in full control, even on autopilot.
However, as you had observed in the comparison between the Dehler 43 and the Opium 39 , narrow fast performance cruisers will have a better performance in light winds and if you noticed that the Dehler 43 had a better performance than the Opium in what regards that, on more modern and faster sailboats like the Salona 41 or the Luffe 40.04, that difference will be even bigger.
That has also been showed on that recent big test by Voile magazine where a Pogo 30 had a similar performance of a winner 9.00 in light winds, being the Pogo a much more lighter and sportive cruiser than the winner, with a much better overall sailing performance. Te winner has a much narrower hull, and certainly, as the Pogo, a very well designed hull.