Hi Surfnsun,
If you go to a better retailer or manufacturer … they will “educate” you much more than “sell” you and will put your legitimate best interests above their profit.
I would start with reading the information in the tutorial post so that you have a much better idea of the most important parts of a mattress purchase.
It also has more information about testing mattresses so that you don’t go by the very subjective “showroom feel” of a mattress alone which often doesn’t translate into a mattress that works well in “real life” when you sleep on it on a regular basis and can have lower odds of success than random chance alone (see this study).
Even if you buy a mattress that is a great match for you in terms of PPP … it would have little value to you (especially in that price range) if there are lower quality materials in the mattress which will soften or break down too quickly and lead to the premature loss of comfort and/or support and the need to replace the mattress and which isn’t covered by any warranty (see post #174 here).
Phoenix