I have a firm queen size Serta mattress. I need the firm for back pain, but it does feel like sleeping on pavement even with an eggshell foam topper. So I was looking for something that would feel soft without sacrificing the firmness. The Margarita Down Alternative Mattress Pad fit perfectly. It gave me a softening layer that cradled my body and made drifting off to sleep easy. The mattress pad stays in place, I toss and turn all night and I no longer wake up sweating and aggravated. One caution, my mattress is only 6 inches thick, the foam pad 1 inch, and I had trouble getting it on, so be careful if you have a very thick mattress. This mattress pad is definitely a 10.