Hi PSDC,
Welcome to the Mattress Forum! 
You can see some of my comments about Plushbeds in post #2 here. A forum search on Plushbeds (you can just click the link) will bring up much more information and comments/feedback about them as well. They generally use good quality and durable materials in their mattresses and they would certainly be a much “better than average” choice compared to most of the mainstream mattresses that most people end up buying. However, they do a lot of internet advertising so they do attract a lot of online attention with large “discounts”, so I would make some careful “value comparisons” with some of the other options that are available to you because they may not be in the “best value” range for many of the members here that are aware of the many other similar options that are available to them.
Another option you may wish to consider is to look online and use the experience and expertise of the members listed in post #21 here who are all very experienced and knowledgeable and specialize in providing the type of help and guidance on the phone that can help you make good choices. There are a wide range of latex option included in the choices there and I believe that all of them compete well with the best in the industry in terms of their quality, value, service, and transparency.
Their detailed knowledge of their mattresses and how they fit with different body types and sleeping positions along with your feedback from local testing, a customer base of many people that they can use as reference points, and any exchange, return, or any options they have available to customize a mattress after a purchase can help lower the risk of an online purchase. These online retailers or manufacturers can also be a good “value reference” for local purchases to make sure that if you are paying a “premium” for a local purchase (in exchange for the kind of “in person” guidance, service, and value that comes with dealing with a local retailer that can help you make more “accurate” choices that you have tested in person) is not too high.
Phoenix