Hello -- This is the kind of question we get quite a lot. The problem is that there is no good answer to it. Both Sealy and Simmons make a large variety of product lines that span pretty much all price points, and each line comes in a wide array of comfort options. So broadly speaking, each brand will have at least one model (probably more) that is a good match for you from a pressure relief and spinal support perspective.

That said, each line they offer is also going to have additional features that will affect the price. Sometimes you'll have to decide whether you like or dislike these features (eg, the slow sinking feeling of memory foam). In other cases, there will be nothing not to like -- you'll just have to decide how much the features matter to you (eg, motion isolation, edge support, etc.).

No matter which brand you choose, you'll also have to decide whether you want more foam padding (which will likely settle and form "body impressions" over time), or less foam padding (which may mean slightly less comfort and pressure relief when the mattress is new).

Large national brands like Sealy and Simmons tend to offer product lines with the features that are most popular amongst the largest number of people. So unless you're looking for something specific that neither brand offers (eg, an organic mattress, or an all-latex mattress), you'll probably find that both Sealy and Simmons have a bed with features you like.

Net, to find the mattress that's right for you, you should start by finding the model(s) from each brand that are the best match for you in terms of pressure relief and spinal support. Then, from among those models, choose the one that offers the additional features you like and/or care about at the best price.

I hope this helps!