Hi gate25,
I would first give it a little bit of time more than just a few days to make sure that your initial perceptions are more predictive of your longer term experience although with higher weights then you would typically need firmer support and comfort layers than others who are lighter. The key is not so much whether you are sinking in too much overall but whether you are sinking in evenly and this will depend on your body type and weight distribution and on your sleeping positions. If your pelvic girdle is sinking in too far relative to the other areas of your body then it can “tilt” the pelvis and change the curvature of your lumbar spine away from it’s neutral alignment which in turn can lead to lower back discomfort or pain as you are experiencing.
If after a few more days it becomes more clear that this is predictive of your longer term experience on the mattress (there is both an adjustment period for you and a break in period for the mattress with any new mattress purchase that generally takes a few weeks), then changing to the Pamper will improve primary support because it will “stop” your hips/pelvis from sinking in as far and would probably lead to better overall alignment in your lower back.
The challenge with this is that you could be trading one “symptom” for another because the comfort layer in the Pamper is thinner (only 2") and is quite soft for your body weight (21 ILD) so you may “go through” it more into the firmer support layer underneath it and this may lead to symptoms connected with pressure relief on your pressure points (generally hips and shoulders if you are a side sleeper). You may also need more thickness in the upper layers to “fill in” the recessed gaps in your sleeping profile firmly enough to provide the best possible secondary support under the inward curve of your lumbar spine on your back or under the narrower waist when you are on your side.
So the odds are much lower that you will sink into the Pamper “too much” because the support layer is firmer and there is less thickness in the softer comfort and transition layers above it for your heavier parts to “travel” before they are "stopped’ by the deeper support layers but you may also be increasing the odds that your lighter wider shoulders may not be able to sink in enough for the best pressure relief before they are “stopped” as well by the firmer support layers or that the top layers are not thick enough to provide the firmer contact and secondary support under the inward curve of your waist to help maintain alignment.
In this case as you mentioned you could add a topper that was the thinnest and/or firmest that was likely to provide you with adequate pressure relief and so that your odds of neutral alignment were higher than they would be with a thicker softer comfort layer where you could sink down into the mattress unevenly.
One of the difficulties of the PLB “natural” and “all natural” lineup is that all of them except one (the Nutrition) use quite soft latex in the top comfort layers and their toppers are even softer yet which can be very “comfortable” in a showroom but are not as suitable for higher weights IMO as a firmer comfort layer would be. People who are heavier will sink more deeply into firmer layers than those who are lighter so they will feel softer to them than the same layer would feel to a lighter person. This is why heavier people generally need firmer layers all the way through the mattress.
You can see the specs of the PLB lineup here and as you can see the Nutrition is the only one that uses what is called a “dominating layer” which means it has a firmer layer over a softer one (which is why it feels firmer than the Nature for most people even though it is thicker). It still has 2" of softer latex underneath it but the top 3" are firmer which means it may be more suitable for higher weights although the soft layer would still allow you to sink in further than it would if it was firmer … even under a firmer top layer. You could “approximate” the Nutrition with the Pamper and a 3" talalay topper in the range of 28 ILD if your experience on the Pamper indicated that the comfort layer was too thin and soft to provide enough pressure relief. Your other option would be to add a topper that was a little thinner and “just enough” in terms of thickness and softness to allow your shoulders to sink in enough with less risk of alignment issues under your hips/pelvis.
Overall … the Pamper would be less “risky” in terms of alignment and would provide more options in terms of customizing and fine tuning the thickness and softness of the comfort layers but would still contain more soft latex than may be the 'ideal" for your weight It’s always “safer” to choose a firmer mattress than a softer one because it’s easier to add softness/thickness to a comfort layer by adding a topper to it than it is to improve the primary or secondary support of a mattress where the support layers are too soft or the comfort layers are too thick or soft because this would generally mean that layers in the mattress need to be removed or exchanged rather than using another layer on top of them.
So if your experience over a few more days (it’s generally better to sleep on a mattress for a minimum of two weeks or longer before “assessing” it for its suitability) continues to indicate that your back issues aren’t improving then the Pamper would be a less risky choice out of the two you are considering.
Just as a further note … I would personally make the PPP (Posture and alignment, Pressure relief, and Personal preferences) of a mattress more important than its cost or type of material because the performance of a mattress is more important even than the quality or value of the materials inside it. If you have higher quality materials that don’t perform the way you need them to then they would have little value to you anyway unless you had options available to fine tune it in the direction you needed to make changes. If a lower cost mattress was more suitable for my needs and preferences than a more costly one and it used good quality and durable materials for its price range then I would certainly give it strong consideration if it was more suitable in terms of PPP but of course this would depend on your ability to either test it in person or still have good fine tuning or exchange options available to you after the exchange.
It would be much more risky going by “theory” in a mattress exchange where you couldn’t test the new mattress if it didn’t work the way you expected and you didn’t have any further good options available to you (such as adding a topper if it was too firm). I would be quite hesitant to exchange for another mattress that was a complete “unknown” that you couldn’t test carefully and objectively for PPP (or at least were confident that if anything it would be too firm and you could add a topper) before you made the exchange if it was your final chance to exchange it.
Phoenix
