I am in the market for new mats as the crib mattresses I use now have cracks and are taped and while the sheets cover that I know it is just a matter of time before it becomes an issue. I have dickered between cots or mats but even without knowing I wondered just how comfortable the fold up ones would be because I could see some child's hip or knee or elbow getting stuck in the crack and it being annoying. I did see some that were a three fold rather than four so at least the hips would be on something solid for at least most kids. Then I realized by the time I folded up five mats they would take up the same if not more space than stacking 5 mats. I just wish the mats were longer as even now using the crib mats I see 3 year olds that lay straight and toes are at the end so on something only 40-48" they for sure would have to curl up although being thin the toes would just rest on the floor I guess. Even the cots are no longer so at least with the mats the feet aren't on the frame. Then again I have considered just buying new crib mattresses or getting foam toppers and covering them myself.