Hi ivanrajkovic,
When I talked with Joe Alexander a week ago (the day before he was getting married by the way) he was telling me about his new Alexander line and he was very excited about them.
I know they use good quality materials but I don’t remember the specifics off the top of my head so you will need to ask them to find out the type and the quality/density of the materials inside it. They will be the most reliable source for this type of information. If you can find out the information listed here and post it on the forum I’d be happy to make some comments about the quality/durability of the materials and the mattress as a whole.
There is also more about the most important parts of the “value” of a mattress purchase in post #13 here that can help you make more meaningful quality/valuecomparisons between mattresses.
Phoenix