Trying to find someone who has sailed both would seem to be a challenging task.
However, using
https://sailboatdata.com you can compare the specs of related boats. A quick check indicates that the Mouette 19 falls between the Rhodes 19 and the DS. Length and beam more like the Rhodes, displacement more like the DS and sail area somewhere in-between, although closer to the DS.
The sail area / displacement is almost the same as the DS, meaning it will sail slower in very light winds (more wetted surface, because longer), but a bit faster otherwise (slightly higher hull speed). Would seem to me that the Mouette and the DS fit a similar niche, although the former can probably stow even more gear if you are into boat camping. (All this from the spec data)