How long will a plush boxed mattress last?

Durability scores 5.4 out of 10, its lowest axis, and the comfort layer is the reason. The 630-coil core of heavy 13.75-gauge tempered steel resists sag and carries a 10-year warranty, but a plush bed leads with more soft foam, where body impressions form first over years. Expect the structure to stay sound while the surface gradually softens, the normal life cycle of any plush mattress. A protector and rotation help.