Hi re-vogel,
Restava can provide you with specifics for each mattress but they use a combination of 4.2 lb and 5.3 lb memory foams.
I don’t pay a lot of attention to warranties (see post #174 here) and more to the quality of the materials in a mattress which are a much more reliable indicator of the useful life of a mattress but you can see the details of their warranty here.
Phoenix