I purchased this mattress based on the advice of the customer service person. I am a stomach sleeper and he said the soft one is for side sleepers and should work for stomach sleepers.I got it and started sleeping on it 10 days ago. I have had back pain every morning when I wake up.I spend over 90% of my sleep time on my stomach. I should have got a medium or firm.Then, when I contacted customer service, they simply said, "They are not returnable."You know, I've bought stuff here before - even bought this mattress for a friend (medium) who said he liked it but it was a bit too hard. And this site is great but I am very disappointed in MY product.Will end up donating this and buying another from somewhere else.By the way, when I contacted customer service on line help just now, she said, "Stomach sleepers need soft." That's incorrect. I've been in sports medicine for over 22 years. Stomach sleepers are keeping their back in too much flexion for too long an extended period of time.BEWARE! DO NOT rely on the assistance of these customer care people. They have NOT done their research!