Hi jasonsmith,
The answer to this is in some of the links in the “read first” post I linked earlier and in my reply to the same question in post #4 earlier in this thread.
You can test for the feel and performance of a mattress in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences) with good objective testing but the durability and useful life of a mattress is something you can’t feel in a showroom and for this you meed to know specifics of all the components and layers including the thickness and density of any memory foam or polyfoam in the mattress.
With memory foam and polyfoam … higher density equals greater durability. You can read more about some of the other factors that affect the useful life of a mattress in post #4 here and the minimum I would look for are in the previous post.
Better manufacturers or retailers will already know all of this and use a more educational and factual approach in their mattress sales (vs a marketing approach) but if you are dealing with someone that isn’t familiar with the quality of the layers that are in their mattress or how to tell then if you post the specifics on the forum I’d be happy to look and see if there are any obvious weak links in a mattress you are considering. If you aren’t able to get the specifications of a mattress from a retailer or manufacturer … I would pass the mattress by because you would be making a blind purchase with no way to know the quality or durability of the mattress you purchased.
Sleepdutchcraft is one of the manufacturers mentioned in a number of posts on this forum and a forum search on Dutch Craft (you can just click this) will bring up more about them. They make some good quality and value mattresses and more importantly will tell you what is in their mattresses so you can verify the quality and make meaningful comparisons with other mattresses.
Phoenix