My Fiance and I purchased the "buy one get one free" Serta Pillow Top Mattresses a year ago in late March, 2008. My fiance noticed right away his mattress was starting to sink where he sleeps. Gradually over the months he started to have a crater in the mattress and was having back & neck problems (actually needed prescription medication for his neck!) My mattress started to sink as well, but not as badly as his, at first. I have a queen and he has a king. Not sure if the mattress size makes any difference. We are not large people. We are normal for our height/build. We have been discussing what the warrenty/guarantee on the mattresses might be and he decided to go on line and see if there were any other people complaining. What do you know? There were, and A LOT. All with the exact same issues. Why hasn't this company had a recall on these defective mattresses? And what the heck do "stains" on the mattress have to do with sagging? They say "stains" would void the guarantee for a refund. That's ridiculous. That's not the issue. Are they really going to re sell a mattress with a huge sag in it if it doesn't have a stain on it? I think they knew there were problems with these mattresses and they also knew people would get stains on them, so they protected themselves by adding this disclaimer. We too would love to hear from anyone of you out there who has any suggestions or have had any satisfying results from this issue. If there is a class action suit started, count us in.