Hi Vik,
You can see some of my comments about Extreme Mattress and some comments about Dutch Craft (which is an Amish manufacturer that they carry) in post #4 here and in post #29 here.
There is also more about the most important parts of the “value” of a mattress purchase in post #13 here.
Outside of careful testing for PPP (Posture and alignment, Pressure relief, and Personal preferences) hopefully using the testing guidelines in the tutorial post … the most important part of the value of a mattress purchase is knowing the type and quality of all the materials and layers inside it regardless of the name of the manufacturer on the label.
If you can provide the specifics of the mattress you are considering (see this article) and post them on the forum I’d be happy to make some comments about the materials or let you know if I can see any potential weak links in the mattress.
Phoenix