Hi nario,
Welcome to the Mattress Forum! 
I’m assuming that you’ve read the mattress shopping tutorial which includes all the basic information, steps, and guidelines that you will need to make the best possible choice … and know how and why to avoid the worst ones.
Two of the most important links in the tutorial that I would especially make sure you’ve read are post #2 here which has more about the different ways to choose a suitable mattress (either locally or online) that is the best “match” for you in terms of “comfort”, firmness, and PPP (Posture and alignment, Pressure relief, and your own Personal preferences) that can help you assess and minimize the risks of making a choice that doesn’t turn out as well as you hoped for and post #13 here which has more about the most important parts of the “value” of a mattress purchase 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 all the other parts of your personal value equation that are most important to you.
While I can’t speak to how a mattress will feel or how different mattresses will compare in terms of comfort and PPP for someone else … outside of “comfort” and PPP the most important part of the value of a mattress purchase is durability which is all about how long you will sleep well on a mattress. This is the part of your research that you can’t “feel” and assessing the durability and useful life of a mattress always depends on knowing the type and quality of the materials inside it regardless of the name of the manufacturer on the label or how a mattress feels in a showroom or when it is relatively new (or how long a company has been in business) so I would always make sure that you can find out the information listed here so you can compare the materials and components to the quality/durability guidelines here to make sure that there are no lower quality materials or weak links that would be a cause for concern relative to the durability and useful life of a mattress you are considering before making any purchase.
There is also more information in post #3 here and the posts it links to that would be helpful for those that are in higher weight ranges. While the process of how to choose a mattress would be the same … most people in higher weight ranges will generally need or prefer firmer mattresses (firmer materials will feel softer because you will sink into them more) and materials and components that are higher quality and more durable (the materials and components in a mattress will soften and break down faster for those in higher weight ranges than they will for someone that is in a lower weight range that doesn’t compress the mattress as much) so I would reduce or minimize the use of lower density materials that would be suitable for people that are in more “average” weight ranges (so if there are any they are only in thinner layers in the range of “about an inch or so”) and focus more on higher quality/density and more durable materials (5 lb or higher memory foam, latex, or 2 lb or higher polyfoam) … especially in the comfort layers of a mattress which are more likely to soften or break down before the deeper layers or components in a mattress. Of course budget considerations can also be one of the trade-offs that are an important part of the “value” of a mattress purchase as well so there may be some people that are comfortable with choosing a mattress with lower density materials that won’t last as long because of the lower price.
I would also make “mattress only” to “mattress only” comparisons because a foundation that would be suitable under any one of the mattresses you are considering would generally be suitable for all of them (although tempurpedic does require that you purchase a suitable solid surface foundation such as their own as part of their warranty criteria) and including a foundation in your price comparisons can skew the comparisons you are making between them.
[quote]1. Novosbed Classic
ADMIN NOTE:Removed 404 page link | Archived Footprint: novosbed.com/product/classic-memory-foam-mattress/
Free shipping. We would have to assemble foundation and move old mattress ourselves.
Good research data. Feel is similar to tempur-pedic cloud prima, but have not tried this.
I like that Novos checks out ok at SLTD & kind of ok here. But I can’t find much more data on them compared to other online vendors. Buying without trying is a small concern here as well.
$1,199.00 for mattress. $1,458.99 for mattress and foundation.[/quote]
As you mentioned this mattress would be similar to the Tempurpedic Cloud Prima so if you are confident that the Prima is a good match for you in terms of PPP then it would certainly be worth considering. They also have a great return policy that lets you test the mattress in your bedroom instead of a showroom with little risk outside of the time you spend sleeping on it or in the “worst case” returning it should that become necessary.
In terms of the quality and durability of the materials it uses 2" of 4 lb memory foam on top of 2" of 5 lb memory foam on top of a 1.8 lb density polyfoam base layer so while there would be no lower quality materials or weak links in the mattress relative to more average weight ranges … I would add a slight caution in your weight range because the 2" of 4 lb memory foam and the base layer of 1.8 lb polyfoam are both “on the edge” and a little lower density than I would normally suggest in your weight range.
NOTE ADDED JAN, 2016: They have now introduced their new simplified choice mattress which has replaced their previous models and have also become a member of this site.
[quote]2. Tempur-Pedic Cloud Prima
https://www.mattressfirm.com/tempur_cloud_prima_10_-p423.aspx
Free delivery, setup, and removal of old mattress.
Good brand and research. Best feeling tempur-pedic at this price range I found.
Didn’t feel like the best in the brand for me, but good at the price range. Looked a little thin. Felt great in one store & slightly too firm in another. I like the brand recognition / research.
$2299 for mattress. $2,799 for mattress and low profile box-spring[/quote]
Tempurpedic no longer discloses the specifics of the foam quality/density in their mattresses but as far as I know the Prima uses 1.2" of 4 lb memory foam on top of 2" of 5.3 lb memory foam on top of a 2 lb polyfoam base layer. With the slightly thinner 4 lb memory foam layer and the slightly higher base layer there would be no lower quality materials or weak links in this mattress relative to your weight range but of course all the Tempurpedic mattresses are not particularly good “value” compared to many other similar mattresses made by many of their smaller competitors.
[quote]3. Original Mattress Factory Serenity
Mattress made locally, in store. $45 delivery fee. No returns allowed.
Not much research available. Felt very good in store, but I’m concerned about how long it would last.
I liked the firm but ‘bounce back’ quality, though @Phoenix has stated that may be related to the box spring used.
$1,799 for mattress. $2,099 for mattress and boxspring [/quote]
While I don’t know how this would compare for you to the Novosbed Classic or the Tempurpedic Cloud Prima in terms of feel, firmness, or PPP (your own testing will tell you this) … you can see the specs of the Serenity in post #14 here. It uses 8 lb and 5 lb memory foam and a 2,25 lb polyfoam base layer which are higher quality/density and more durable materials than either of the other options you are considering and there are certainly no lower quality materials or weak links in the mattress that would compromise its durability or useful life.
I would also tend to use any memory foam mattress on a solid non flexing foundation or platform bed rather than on a box spring that flexes but I would make sure you test the mattress on the same type of support system you would be using underneath it at home (testing it on an adjustable bed would also be the same as a solid non flexing foundation) because a box spring that flexes will definitely have an effect on the feel and performance of a mattress on top of it.
The better options or possibilities I’m aware of in and around the Virginia Beach, VA area (subject to making sure that any mattress you are considering meets the quality/value guidelines I linked earlier in this reply) are listed in post #2 here.
I hope this helps and I’m looking forward to finding out what you end up deciding.
Phoenix
