Looked at these type of mattresses. Thought if it’s try for 100 days return then do it.
Did it, had a bad back the first night thought eh up. But no it was fine the next night. Must have been me getting used to it. All all a better night sleep ever night.
Only thing I would point out is that if you don’t like the mattress you have to return it. It is in the small print when you get the mattress.Try doing that and getting it back in the bag and box. 
But honestly you shouldn’t have to