These have been great for the winter months. I purchased them for my daughter for bed time and they are warm, I wish they made thick cotton ones instead of fleece, they are really stuffy if the heat is on.  My daughter ends up sweating through the night sometimes.  But for those really chilly nights, I am really glad I have these!  I wish they had a cotton version though... even better a down sleeper!  Now that's an idea!