I have 2nd $1300 pillow top serta king mattress within 1 year. Both formed sinkholes on both sides. Wake up with sore backs. What junk. I am going for my money back or exchange for a good old plain firm mattress. Probably will end up putting this out to the curb, and write it off as a loss. Where do we go from here after 2nd replacement... junk junk serta products stink just like the wet sheep on their products .this seems to be the standard complaint from many people who own this junk. Can’t wait to get rid of it real soon