We bought a Spring Air mattress and box springs from RC Willey. After 3 years we had sagging on both sides. We turned it but because it is a pillow-top we could not flip it. They sent someone out and it had only sunk 1 1/4" so, in their opinion, it was not a defective mattress. The store did not back us and this huge distributer said they could not do anything for us. read full review »