Hi whitesox20.
I am glad you are having fun shopping and researching for your mattress. 
Thank you for confirming the source of specs for the Essential.
You are correct that all these mattresses will have a longer useful life than the 5 years criteria you are looking at. All the options you are considering are using durable good quality materials and there are no lower quality materials or weak links relative to more average weight ranges. What may help you differentiate between them is considering the feel that is most attractive to you in terms of preferences and needs. Addable with its 2" memory foam will have great pressure relieving qualities but have much less of the resilience and bounciness of either BME, or Ghost offer. BME will have a more buoyant feel and Ghostbed with the 1.5" latex layer will borrow a bit of the “dead” feel of the 2" Memory Foam below it.
In terms of comfort it may be worthwhile noting that out of the three options you are looking at, BME offers 3 different firmness choices (Soft, Medium, Firm) while the other two of your finalists have single firmness mattresses and it may be worthwhile calling and having a more detailed conversations with each of the manufacturer/retailer to determine if what they offer would be suitable for you in terms of PPP (Pressure relief, Posture and alignment and your own Personal Preferences)
As for “worth”, while price is certainly important of course … the “value” of a mattress purchase is what is most important and price is just one of many factors that can affect the “value” of a mattress purchase. There isn’t a “formula” that can be used to assess or “calculate” the value of a mattress because there are so many different variables and criteria involved that can affect the price of a mattress that can each be more or less important to some people and not to others who may have completely different criteria or definitions of “value”. I guess that a better question to ask is if based on you personal value equation the $200 difference in price is worth to you. Of course that part of the value of a mattress purchase is also relative to how a mattress compares to the other finalists you are considering, but there are many reasons that a mattress that may be “good value” for one person may not be good value for someone else that has very different needs and preferences.
There is more about the 3 most important parts of the “value” of a mattress purchase in post #13 here which can help you make more meaningful quality/value comparisons between mattresses in terms of suitability (how well you will sleep), durability (how long you will sleep well), and the overall value of a mattress compared to your other finalists based on suitability, durability, and all the other parts of your personal value equation that are most important to you (including the price of course and the options you have available after a purchase if your choice doesn’t turn out as well as you hoped for).
My role is to provide some accurate information and perspective to the process of deciding on “value” so that each person can find for themselves which of the many parts of a mattress purchase and different types of mattress materials, services, and outlets represents “great value” to them and help them make more meaningful comparisons rather than create a formula that determines value for others (which I don’t believe is possible or even desirable).
Neither one of the options you are considering would be a “mistake” in terms of quality and durability but nobody else can feel what you feel on a mattress and only you can decide which of them you are most likely to prefer and which one you believe is the best value for YOU regardless of whether it may be the best value for someone else.
Phoenix