Our King Koil King Mattress is two years and it is completely broken down.  There is a four inch dip on my husband side and a two inch dip on my side.  Representatives from the service center inspected the mattress and they stated that it was definitely defective but due to a small water stain on the side of the mattress, the warranty was void.  It is basically a piece of junk.  Don't ever buy a King Koil!!!