I sent a mattress for sewing of small tear on the top joining corner last year (May 2010) when the mattress came back, the bottom sheet was different and the mattress had lumps in it. (The bed was bought in August 2008) It was re-fetched by the factory for fixing. I believe and mentioned to Serta that the mattress that came back from sewing is not the same mattress that I bought and that it was changed. When I complained that the mattress had lumps after being sewed, they fetched the mattress for fixing of the lumps. These lumps have... read full review »