We bought a top-of-the-line King Koil latex mattress. It was soooo comfy for the first 30 days or so and then we started to notice obvious sagging, waking up with back pain, etc. We removed all of the bedding to look at the mattress and the sagging was actually visible and looked like the mattress had been folded in half, almost leaving a crease across the middle. Fortunately, we were working with a GREAT furniture sales company who promptly went to bat for us with King Koil. Without even looking at the mattress to see the failure of the latex, King Koil said we just needed a firmer mattress. They sent us a replacement mattress and it was much firmer...so firm in fact that we never would have purchased it had we had an opportunity to lie down on it at the showroom. We decided to give it a chance but this time in less than 30 days the latex started to cave again. We even took photos of it by placing a bowling ball on the mattress to illustrate how far it sank into the mattress at various spots. Our salesman did agree to take back the bed and give us store credit, so this is not a reflection of the service received in any way. They were wonderful! It is instead a reflection of the extremely poor quality of the King Koil latex mattresses. Two different models over two different months and they both started caving in within 30 days. It's a shame because for the first 30 days we were so happy with it. We encourage you to pass on King Koil.