I am a hot sleeper and have read a lot about temperature regulating mattress pads.  I was skeptical that a mattress pad could actually help me sleep better, but I decided to try it.  I am so glad I ordered the mattress pad.  Before the mattress pad I would wake up a few times during the night very sweaty and hot.  Now I sleep the entire night through. Of course, nothing is perfect.  It doesn't keep you cool in the sense of the word "cool", but it does somehow keep you from getting super hot.