Hi a2b1c3z1,
Therapedic is a licensee group of independently owned factories and they make different mattresses in different areas of the country and in some cases the specs of a mattress with the same name can be different. Many of them also make private label mattresses that are unique to certain stores. This is why most licensee groups (see the top 15 list here) don’t list most of their mattresses that are available across the country on their main website.
Eclipse and Eastman house are owned by Mattress Development Co. and their main factory is Bedding Industries of America which is also a Therapedic licensee so Eastman House, Eclipse, and Therapedic are all made at the same factory.
If the mattress you are looking at is 8" thick (so you know there are no polyfoam layers above the latex), then the mattress would be roughly comparable to any other mattress that used a similar 6" + 2" latex design that used the same type of latex and had a similar cover regardless of the manufacturer (although another mattress may have different firmness levels for each layer). If the mattress is more than 8" thick then there may be some additional layers (possibly polyfoam quilting layers above the latex) which could be a weak link in the mattress if they are more than an inch or so of lower density polyfoam.
Their website lists the following layers for this mattress …
Natural Serenity Plush:
Cover:
Natural bamboo stretch-knit fabric cover is healthy, anti-microbial,
sustainable, organic & breathable
The quilt layer:
safeguard fiber
1 ½" high-density convoluted foam
1" enhanced plush foam
2" of talalay latex for extra plushness
firm 7" talalay latex core.
If this mattress is about 11.5 - 12" thick then these would include all the materials. As you can see … there are 2.5" of polyfoam above the latex and if these are lower density layers then it could be a weak link in the mattress. It’s also unlikely that the Talalay core is 7" thick since Talalay is poured in 6" layers so it’s more likely that they meant 7 zoned rather than 7".
Either way … I would want to know the density of the polyfoam and would tend to look for thinner polyfoam quilting layers in a latex mattress.
With any online purchase where you can’t test the mattress before you purchase it I would make sure that you have a more detailed conversation with an online retailer or manufacturer so you are confident that a mattress would be a good match for you in terms of PPP and the firmness of the support and comfort layers. I would also make sure you are comfortable with any options you have both before and after a purchase to customize or exchange the mattress or individual layers in case your sleeping experience indicates that the mattress isn’t the best choice for you.
I would also compare these to some of the members here that sell similar 6" + 2" latex mattresses online (there is a link to a list of these in the tutorial post) that you can use as a “value comparison” based on the parts of your personal value equation that are most important to you.
The better options and possibilities I’m aware of in the New York City area are listed in post #2 here.
If you follow all the steps in the tutorial post one at a time without missing any you will be fine 
Phoenix