Hey tzzzzz,
Welcome to the Mattress Underground, glad to have you here.
I will be brief as you seem to have a grasp on the shopping for a mattress system experience.
Your assessment of the BR Cushion Top Medium is spot on regarding the red flags. There is also the issue of the foam encasement around the coils. I think most folks do better with an quality edge to edge coil support system. Plus the fact of the BR comfort system will feel good right away, but tends to soften over time with no way to recover the feel it once had. Which brings me to the S&S.
The S&S uses a reinforced coil edge and has incorporates a lumbar support in the center of the mattress along with the latex and wool comfort layer. Remember, latex is a foam, foams will soften a bit. Of course, latex will offer more resilience and bounce than the ve foam of a BR, but latex will provide you will a bit of longevity that you are looking for. The wool layer over the latex along with the enhanced lumbar support in the S&S are probably what you are feeling initially. It will soften a bit. So, you need to go with a little gut instinct as you have tried the mattress and imagine what it will be like a month down the road in terms of firmness.
Toppers are a very popular way to tone down that initial firmness and add longevity to the mattress. I would suggest if you decide on the S&S, wait a month before adding any additional mattress segments. You really want to know if it will tone down by itself. Also, another factor in buying a new mattress, is you and your body! It may take more than a New York minute for your own body to adjust to the feel. Testing the mattress in the showroom, even if you bounced around on it for 20-30 minutes does not compare to eight hours a day, for a month. Body impressions, softening, rotating the mattress, finding your comfort spot on the mattress are all a part of the adjustment curve. You are simply not used to it yet. That is where intuition comes into play.
You know your body better than anyone. Remember your 3 R’s. Refund, Return, Restocking Fee policies. Go over them wherever you decide to make a purchase. Negotiate if needed and get it in writing. Every sale can be individualized. Perhaps if they are confident enough in the performance of their product, and they feel it is a good match, they would be willing to enhance their 3R policy in a way that you are protected for a reasonable period of time, 60, 90 or perhaps 120 days if that is not included already.
Good luck with your decision, I believe quality is more often the better choice.
Norm
***Just an afterthought as I re read your post:
Recently while travelling I slept for a week on a sleep country bloom mattress:
Which I found very comfortable, as it was soft, yet firm enough to not aggravate my back (though long term who knows).
After sleeping so well last week I have decided to bite the bullet and buy a mattress. I have read through the full tutorial on buying about all of the materials etc and feel well informed.
Many times we are enticed by a mattress we experience on a vacation or at a B&B.
There are many factors to consider. Usually, if the mattress you left home is not so great, any mattress will seem like heaven, even if it is moderately better. We often believe we had the best nights sleep on vacation, when in reality, the experience just points out, the mattress we have at home has seen it final days.
When on vacation, we are often occupied with long airplane rides, driving distances, or even work conferences, that by the time you are ready to hit that mattress, you are so exhausted, grandma’s pullout couch seems like heaven.
You don’t know the history of the mattress. It may have been the firmest mattress on the market at the time of sale, and now after 100 folks have slept, bounced, kids jumped, and whatever else goes on, has changed the disposition of the mattress.
More often than not, the mattress you purchase from the “hotel’s” website feels nothing like the version you get shipped to your home. That is not to say, you may have picked a winner, it just means you need to factor in a variety of considerations when going that route.