I have used my Combat Nato little more now, during this weekend about 40 km skiing. It has been snowing rather much during previous week so I tested deep snow skiing more with my Combat Nato.
It really depend on the snow characteristics if one sink through the snow or not. On many places I sank maybe 30 cm into the snow with my Combat Nato (210 cm, my weight is 80 kg), on other places where the snow was more packed I sinked just down through latest snowfall (about 10 cm). I really do not know what skis to be used to not sink through softer deep snow, but they must be rather wide I'm sure. Maybe there are some hunter type of skis out there that is suitable for such conditions.
I do not recomnmed anyone skiing alone longer distances in softer deep snow with Combat Nato if You will sink deep into the snow. It is rather demanding on the body since You basically have to step forward. It just do not work to try to get the ski to penetrate the snow down under the snow cover if you sink deep. You then have to more or less crush the snow from upside-down-forware step by step. If You are a group of skiers with Combat Nato skis the following skiiers behind the first "tracker" will get a comfortabe tour. For example I made a ski tour about 10 km in the deep snow and had to plough throuh the snow but back in same track it was a nice ride.
I like my Combat Nato more and more. Now I know their limitations in deep softer snow. When planning longer tours one has to take that in consideration because if you need to ski trough deep soft snow and You sink trough it several decimeters the speed forward will be slow, it will be even slower then normal walking speed.
Although I have not tried to ski in a track made by Combat Nato ski with skis not not so wide as Combat Nato I would guess I could ski without problem with my Asnes Amundsen Fram WL in same track without sinking trough the track, in a fresh track that has not hardened by cold. It is a slight risk when one skier use wider skis and the following skiers use narrower skis that they can sink trough the snow more then the person in front of You with the wider skis.
I suppose the conlusion is as with any ski to now it's limitations or weaker sides and how they behave in various snow conditions. There is simply no universal ski that can perform good in all thinkable snow conditions. But I would be surprised if there are any significant better skis out there then Combat Nato that covers such broad spektrum of snow conditions as it seems they are capable of. At least they are so far good enough for my type of skiing, but keeping the deep snow performance in mind. My skiing is Back Country, mostly Cross Country type skiing, with limited steep up- and downhill skiing. Much sking in forest, over lakes near land, over bogs, fields, moderate up- and downhills. No mountain terrain.
I have still not tried the Asnes X-Skin 45mm NATO Nylon and Asnes X-Skin 40mm RACE that I have. It is so few tours for me that involves very deep climbing but I have one trail that I somtimes ski that has long deep uphill climb. It would be interesting to test the skins there, and also the flat terrain skiing on at least the X-Skin 40mm RACE to see if I notice any speed decrease.