Does anyone have a recommendation for a king mattress for a mostly side and back sleeper? I like it plush but current old mattress is leaving me in pain in mostly my shoulders. It’s an old beauty rest. It was very comfortable at one point. My stats are 5’10" and 240 lb male. It needs to be affordable. I’m looking at the Costco premium ridge crest plush by sealy. Think that would do the trick?
Hey mtp4273,
Welcome to the Mattress Underground 
! Thanks for your question.
There are quite a few mattresses that fit that would suit those requirements, mtp4237. When you describe your current BeautyRest mattress as “old”, how old is it? You like that it has a plush feel; is it a pillow top mattress design in a plush firmness? What model is it? What other qualities do you like about it, and what are some that you don’t?
Congrats on your new mattress shopping journey ! Thanks for including your personal stats for review, mtp as they will help determine what materials and constructions would be best suited for your personal preferences. Higher body weights/ a higher BMI will compress the layers in a mattress more deeply than lighter body types/ a lower BMI, so these individuals will generally need more durable and firmer materials in the upper layers than those of lower weight ranges for the mattress to maintain its comfort and support for a similar length of time. The Sealy Premium Ridge Crest Mattress for Costco is a 14" innerspring mattress using layers of proprietary foams and gel memory foam in the comfort layers. I was not able to find any of the product specs for understanding the mattress’s durability/ comfort and support potential for your higherBMI profile, so you should confirm those before purchase. You would want to ask what are the type foams used in the comfort layers and what their densities are, as well details of the coil support core (wire gauge, height, diameter, number of turns) to better understand if this one would be a good fit for you. You will also want to review Costco’s Return Policy and understand how product warranties are processed before a purchase is made.
You may find a quick review of these Phoenix articles helpful: "The Basic Functions of a Mattress"is a good primer before starting your mattress research; “Mattress Specifications You Need to Know” offers a more in-depth review of the research questions above; and “Finding a Great Mattress Outlet” provides a checklist of questions to guide you through working with a mattress manufacturer. Hope this provides a starting point for your research and feel free to share your updates as you move along the path to better sleep 
.
Thanks,
Sensei