They will be able to verify what I said about Big Mattress and will be up front with you about the exact materials and process they use. Check and see if there are any family owned business in the area that manufacture and sell original mattresses themselves. In my opinion, the only place you can find a quality mattress is from a local manufacturer. Their entire business model is built on lying to customers and scamming them out of money. Completely the manufacturers fault, but they're trying to force me to keep the free adjustable base and pay for it. Within a week the 'firm' mattress was already caving in and not supporting my body.
I am going through an absolute nightmare with Mattress Firm right now because I fell for the BeautyRest trap. Do yourself a favor and avoid Mattress Firm and all other national mattress brands at all costs.