Hi Martin,
You can see some comments about Winkbeds along with some of the other simplified choice mattresses in post #2 here of the simplified choice topic.
There is also more information in post #9 here about the different ways that one mattress can “match” or “approximate” another one. Every layer and component in a mattress (including the cover) will affect the feel and performance of every other layer and component and the mattress “as a whole” so unless you are able to find out the exact specifications of all the layers and components in the mattress you slept on in France (which would be unlikely) and then find another mattress that uses exactly the same type of materials, components, cover, layer thicknesses, layer firmnesses, and overall design (which would be even more unlikely and closer to impossible) then there really isn’t a way to match one mattress to another one in terms of “comfort” and PPP (Posture and alignment, Pressure relief, and Personal preferences) based on the specifications of the mattress.
Mattress manufacturers generally try to differentiate their mattress from the mattresses made by other manufacturers and don’t normally try to “match” another mattress that is made by a different manufacturer so while you may find similar mattresses that use “similar” materials or designs and there would probably be many others that are in a similar general category (see this article) … it’s very unlikely that you will find another mattress that is specifically designed to “match” or “approximate” the mattress you slept on in France so the only way to know how two mattresses compare for you in terms of how they “feel” or in terms of firmness or PPP would be based on your own careful testing or actual sleeping experience on both of them.
Down and feather toppers or featherbeds can add some “cush” to the surface feel of a mattress but they compress so easily that they just add a little bit of cushioning directly under pressure points and don’t do a great job at redistributing pressure along the larger surface area of the body or providing support under the more recessed areas of the body (such as the small of the back for back sleepers or the waist for side sleepers). They are also a higher maintenance item and need to be fluffed up on a regular basis because they pack down and compress with use. In other words they would feel very different from the foam and the microcoil that is used in the comfort layers of the Winkbeds. Down and feathers are more of a “feel” item that is only suitable for using as a topper because of its softness and so it can be “fluffed up” on a regular basis. The mattress you slept on in France would also have had other materials and components inside it underneath the down that would affect how it feels as well. If you like the feel of sleeping on a down topper you could also add one it to the mattress you purchase as well and there is more information and links to some sources for down and featherbeds in post #2 here).
I have never slept on a Winkbeds or on the mattress that you slept on in France so I don’t have any idea how they would compare but when you can’t test a mattress in person then the most reliable source of guidance is always a more detailed phone conversation with a knowledgeable and experienced retailer or manufacturer that has your best interests at heart who can help “talk you through” the specifics of their mattresses and the properties and “feel” of the materials they are using (fast or slow response, resilience, firmness etc) and the options they have available that may be the best “match” for you based on the information you provide them, any local testing you have done or mattresses you have slept on and liked or other mattresses you are considering that they are familiar with, and the “averages” of other customers that are similar to you. They will know more about “matching” their specific mattress designs to different body types, sleeping positions, and preferences (or to other mattresses that they are familiar with) than anyone else.
Phoenix