Moving to Twin XL from all latex King - uncomfortable now and looking to fix

My wife and I have been sleeping on a 12" latex mattress purchased from a store in MA in 2018. Its components are as below

Talalay Global Latex foam in that mattress:
top layer 3" celsion Talalay 14ILD
transition layer 3"Talalay 24ILD
Core layer 6" Talalay 36ILD
Rayon Fire Barrier
Polyester cover

We also had a Casper topper that we purchased in 2019. From YouTube videos at the time, it looks like it had a 1" memory foam and a ā€˜infusedā€™ latex foam middle then some soft top.

Couldnā€™t recall why we added the Casper topper so removed it and have slept on the mattress alone for past 3 nights.
Wife is tossing and turning all night
I have woken with numb left arm from shoulder down and, this morning, pain across mid back/ribs (thatā€™s a first!)
To me, the mattress feels firm. I prefer a soft pillow top style bed. Wife prefers firm but tossing/turning suggests she is not seeing good comfort either.

Casper going back on but Iā€™m not sure why we are both so miserable on 12" of good quality latex.

The goal is to switch to a split king adjustable. Iā€™m not sure if I need to move to:
Soft Talalay
Soft Dunlop
Med Dunlop
Med Dunlop

Or what changes based on current mattress and pain.

Also not sure what effect adjustable would have on the same latex setup.

Iā€™m 5ā€™7" 170 lb side-sleeper
She is 5ā€™4" ā€”lb and mostly back sleeper

Thanks!

Hi eoren and thanks for the inquiry! Based on the information youā€™ve provided, I think the best choice would be to order the 13" mattress, but request in the ā€œcommentsā€ section at checkout that we ship it as a 10" mattress with 3" topper. Having a top layer that is not encased with the rest of the mattress will allow that top layer enough spatial freedom to move upwards when you lay on it, making for a very plush and enveloping feel. This is what I recommend to customers that are used to pillow top mattresses, memory foam mattresses, or people that are looking for a softer or plusher mattress in general. Aside from that, most toppers have our organic cotton topper cover, which is a thin, stretchy cover instead of the cotton & wool cover thatā€™s on our mattress. As far as the cotton & wool cover goes, please keep in mind that anything you have between yourself and the latex affects the way you contour into the latex, making for a much firmer feel. So having a topper on top of the mattress makes for an even more plush and enveloping feel, not just because itā€™s not being restricted by the mattress cover, but also because you no longer have an inch of wool impeding how much you contour into the top layer of latex. So youā€™ll get a huge increase in pressure relief compared to having all of the layers inside of one cover.

If you choose to go this route, my advice on the layers is to order soft Talalay for the topper, and medium Dunlop/medium Dunlop/firm Dunlop inside the 10" mattress cover. Please keep in mind that our initial recommendations have a 90% success rate (we only have a 10% layer exchange rate and a 3%-4% return rate) so thereā€™s a 90% chance that the above recommendation works perfectly for you.