Hi ngeorfieff,
Most manufacturers and retailers in the mainstream industry don’t list meaningful specs about their mattresses on their sites but a good retailer or factory direct manufacturer will be happy to provide them for their customers. Since a mattress is only as good as its construction and the quality of the materials inside it (regardless of the name of the manufacturer) … if the store you are dealing with can’t (or won’t) provide you with this information I would pass the mattress by. There is little “value” in buying a mattress that uses lower quality materials that feel great at first but lose their comfort and/or support prematurely relative to the price you paid and the loss of comfort and support isn’t covered by warranty (see post #4 here).
There are too many unknowns, variables, and personal preferences involved for anyone to recommend a specific mattress for someone else out of all the thousands of mattresses that are available in the market (see mattress firmness/comfort levels in post #2 here). Only you can feel what you feel on a mattress.
“Brand shopping” is also among the worst ways to choose a mattress since all manufacturers have access to the same or very similar materials and a mattress is only as good as it’s construction and the quality of the materials inside it regardless of the name on the label (see post #4 here). The “best” manufacturers or retailers are the ones who are knowledgeable, experienced, and transparent and will put your own best interests above their own. They are the ones that will be willing and able to tell you the quality of the materials inside their mattress so you can identify any weak links in the mattress and make meaningful comparisons with other mattresses.
While it’s not possible to tell someone else which specific mattress to buy … the mattress shopping tutorial here has all the information, steps, and guidelines that can help you with “how” to make the best possible choices … and more importantly know how and why to avoid the worst ones.
Once you get to step 3 in the tutorial … the better options and possibilities I’m aware of in the general Los Angeles region are listed in post #2 here.
Phoenix