we purchased a superking mattress. Within two weeks an extreme raised ridge developed down the centre with puckering of the cover. The manufacturer provided us with a replacement. The same problem began to appear almost immediately. The manufacturer has offered yet another like for like replacement. We are unsure whether to accept this. The man who delivered the replacement said that as soon as a mattress had to be slightly bent to get up the stairs it would never be the same. We are not sure whether to accept the replacement or ask for a refund and look for a new mattress elsewhere. We would be grateful for your advice. The mattress is pocket sprung with a memory foam and wool topper.