Choose HIMARI or SORA when the published dimensions fit your room and you can regularly lift, air and keep the bedding dry. Compare the firmer HIMARI with the fuller SORA by personal preference, storage space and the actual local offering. Thickness alone does not determine comfort.
Details to check before choosing
Measure the usable length and width of the floor, platform or bed base, including any raised edges. Compare those measurements with the exact model and size offered for your country. Then check the folded size and weight, and choose a sheet or cover that fits the same dimensions.
After sleep, lift or stand the shikibuton so you can inspect its underside and the supporting surface. Let both release moisture. Air both faces in a ventilated place, turn the bedding over and rotate it head to foot regularly. Fold and store it only when it is dry.
Sources for this answer
Choosing bedding that moves between two rooms
If a Slovak household needs to move a bed between a bedroom and an occasional guest room, folding can be useful without making handling effortless. Consider the doorway, turning space and any stairs along the route. Check the selected model's weight before deciding that one person will move it regularly. Also identify a place for airing in each room; moving the futon should not mean folding it away while it is still damp.
HIMARI's 210 cm length and SORA's 200 cm length need to fit both supporting surfaces. A shorter spare platform can change which model is practical, regardless of your preferred feel. Compare HIMARI's steadier support with SORA's fuller cushioning as personal choices. Both fold into thirds, but their width still matters when stored. If rearranging rooms already feels burdensome, include lifting and underside checks in the decision rather than counting only the floor space saved.
How do I choose between HIMARI 日葵 and SORA 宙? · How do Japanese shikibuton sizes compare with local bed sizes?