A Lemon or Representative Poor Quality?

My family has 4 Kluft mattresses. I bought one because I had slept on their newest and loved it. I slept on the mattress for a week, and it was brand new. I bought what I thought was the exact same mattress. The mattress that arrived is the most uncomfortable mattress I have ever slept on—including hotels, motels, etc. I’ve owned tufted mattresses, and I have slept on other comfortable Kluft mattresses, but this mattress has the deepest tufting I’ve ever felt. It is similar to when you lay on a towel on the beach, and there are lumps of hard sand beneath your towel. It’s terrible. I called Bloomingdales and Kluft, and I found out that the mattress my family owns had been discontinued (I was not told). The current “equivalent”, my mattress, had actually had layers of latex added to make it more durable. I don’t know if that change has ruined the mattress or if my individual mattress was poorly made and is a defective lemon. To their credit, Bloomingdales has offered a full refund (after a nightmare of a delivery process and months delay), so I am going to exchange the mattress likely for one that is not Kluft. The brand has lost my trust.