Hi jdeck66,
Welcome back! 
I hope that your surgery went well.
[quote]If you could be provide your wisdom regarding the 2 diff beds below
Sleep Science Black Diamond-[/quote]
You can see my thoughts about the Sleep Science 11" Black Diamond mattress in post #4 here.
While the information you posted doesn’t contain much meaningful information, overall it appears that the quality of some of the material is good (with the cautions I mentioned in the post I linked) but they are imported from China and don’t have any certification for VOC’s and off gassing which along with not knowing how long the mattress may have been compressed would be my main concerns (see post #6 here and post #2 here).
As you can see in post #9 here, and as you might remember from some of your other posts, I think highly of Relief Mart and Dr. Rick, they use good quality materials in their mattresses, and none of them have any weak links in their design.
The Opulence uses 2" of good quality 5 lb memory foam on top, then underneath that is 3" of poly foam, and beneath that is the 6" polyfoam core. The core is listed as high density and high resilient, which means it may be 2.5 lb density. While Tempflow uses good quality materials in their mattresses, you’d still want to confirm the density of all of the materials in this (or any other) mattress you might consider from them.
The other concern you would have would be what is recommended for your fusion surgery by your orthopaedic physician. Generally, the concern would be having something that provided adequate support and then “just enough” comfort material on top so as to not allow you to sink in too deeply. Whatever recommendations your surgeon provides should be passed along to Dr. Rick when you come up with a potential mattress design.
Phoenix