Hi NintenTim,
Both the Dreamfoam 12 in 1 customizable ane the BB BestMattressEver use materials that would be suitable for your weight range. The 12 in 1 uses 3 x 3" layers of 2 lb polyfoam and the BestMattressEver uses blended Talalay latex on top of Synthetic continuous pour Dunlop latex latex on top of a 2 lb polyfoam base layer and both of them have covers quilted with a thin layer of polyfoam so there are no lower quality materials or weak links in either one of them and both of them would make a suitable choice.
If you choose the 12 in 1 then it may be worth talking to them about whether they think it would be worthwhile replacing the soft layer with a medium layer because of your current weight.
Both of them have good options after a purchase. With the 12 in 1 you can rearrange the layers and/or use the firmer or softer side of the cover to change the comfort or support of the mattress and if you order from the Dreamfoam site instead of Amazon there is also an additional 10% discount along with the pillow bonus for being a member of this site and they also have a 45 day trial that allows you to return the mattress for a $99 charge which would be the maximum risk if none of the layer combinations works well for you.
With the BestMattressEver you would receive a 5% discount for being a member here and there is also a free return policy if the firmness you choose isn’t a suitable match for you (and I wouldn’t suggest choosing anything softer than the medium).
When you are down to finalists that are all choices between “good and good” (which you are) and none of them have any weak links or lower quality materials in their design (which they don’t) and if there are no clear winners between them then you are in the fortunate position that either of them would likely be a suitable choice and post #2 here can help you make a final choice based on your local testing or mattresses you have slept well on, your more detailed conversations with each of them, your confidence about the suitability of each one, their prices, the options you have after a purchase to change the firmness or exchange or return the mattress, any additional extras that are part of each purchase, and on “informed best judgement” based on all the other objective, subjective, and intangible parts of your personal value equation that are most important to you.
Phoenix