I’m giving this a 5.  It was on sale, had good reviews, is 12 inches thick and feels great.  It’s for my 12 year old son but my in laws spent two nights on it and said it was lovely.  I will probably buy another one for my younger daughters if they have it in a twin size.  Great, affordable, high quality mattress.  No chemical smell.  Came in 3 days and we live in B.F.E