Hi dan87951,
This thread has some of my thoughts about Capitol Bedding (which is a wholesale manufacturer) and Jim at Michigan Mattress (aka TCbedrooms).
The default for the forum search parameters is “a year ago” for the “find posts from” setting but if you change this to “any date” it will pick up on all the posts in the forum.
All three of the mattresses you linked would probably have better quality/value than anything comparable made by one of the mainstream manufacturers and most of these don’t make two sided mattresses anyway so they really wouldn’t have anything that was really an “apples to apples” comparison with these. I would probably tend to avoid the plushest model of the three though because of the greater risk of foam softening with thicker polyfoam layers in this density leading to the loss of comfort or support a little more quickly than the other two choices you have.
Phoenix