Incredibly heavy mattress that developed 'hollows'

This post is for information purposes in case you are thinking of buying a Simmons Beautyrest mattress. Be aware that if you move to another country, there is NO warranty. Also be aware that a Simmons Beautyrest King size weighs around 76kg, and with the monthly turning requirements, unless you are a semi-professional weight lifter, you will need more than one person and there will likely be a lot of swearing involved (mattress has no handles - who MAKES such a heavy thing without handles?). Lastly, be aware that despite many claims to the contrary, the mattress can develop 'hollows' where you sleep that don't go away even when turned according to instructions. We deeply regret this purchase and will most definitely never buy one again.