The lilac topper smells heavenly; slept on it first nite (8 hrs. later); it stays put; I have a 3" Lucid topper in my camper, and it has too much sinkability.  So I thought I would try the 2"; it has made my older mattress more comfortable; but it is not giving me the comfort the 3" Lucid mattress topper does.  I would probably buy the 3" again.  I cannot address the cooling qualities because we keep the house very cool with air conditioning.