I am somewhat of a sheet snob.  I get hot...then cold at night.  I've tried several materials.  Nothing has beaten 100 percent cotton.  These sheets are thick and substantial but comfortable. They appear to be durable, needed for a housefull of grandkids.  The fitted sheet has the elastic all the way around which makes for a nice tight fit.  If you want wrinkle free, Stand guard on the dryer and follow the directions to remove promptly, or buy something other than cotton.  Overall I am very happy with these sheets