Hi Joe Cool,
I’ll see if I can help a bit with the specification differences.
The Tuft and Needle uses 3" of a 2.8lb high performance polyfoam over a 7" 1.8 lb polyfoam core.
The Nest Bedding Alexander Signature Series is offered in three different versions (soft, medium and luxury firm – you didn’t say which model you tried), and each of these models will use memory foam in their makeup, will be tailored as a “traditional” mattress, and have more “premium” foam overall than the T&N, and this would account for the pricing difference, as the T&N is using polyfoam only.
A closer “match” to the T&N would be the Love & Sleep Mattress from Nest Bedding, which is offered in two different versions, Medium and Luxury Firm, The Medium has 3" of 2.8 lb high performance polyfoam, over 1" of 2.0 lb convoluted polyfoam over a 6" 1.8 lb polyfoam core. The Luxury Firm has 2" of 2.8 lb high performance polyfoam over an 8" 1.8 lb polyfoam core.
You can see the specifications of the T&N and the Love & Sleep in post #2 here.
Like with many claims that manufacturers make, it depends upon how the argument is presented and to what you’re comparing. All foam layers being equal, you certainly will have a higher pcf number with fewer layers of foam. Mixing in other foams will change those results depending upon breathability. Memory foam tends to be to least “breathable” of the major foam types.
The layers closest to your skin will have the greatest impact upon your sleeping temperature. There is more about the many variables that can affect the sleeping temperature of a mattress or sleeping system in post #2 here.
This really comes down to your own priorities in choosing a mattress. 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 parts of your personal value equation that are most important to you.
If keeping your price low is a priority, you may wish to focus on the Tuft & Needle or the Love & Sleep. You may even want to throw the Dreamfoam Arctic Dreams into that mix. The Alexander Signature adds more “premium” foams which will provide a different style of comfort, but whether or not that is worth the price to you is again a part of your own personal “Pros/Cons” list.
Regardless of your decision, you’re considering products that use better quality materials and offer good values. All of them also feature a good trail period just in case things don’t turn out as well as you would have hoped. You may already be aware of this, but Nest Bedding and Dreamfoam are members here of the site, which means that I think highly of them and their products.
Hopefully that helped give you an idea of the reasoning for the price difference in the products and can help you make up your mind if one is personally a better option for you versus the other.
I’ll be interested in learning what decision, if any, you decide to make, or if you have any other questions.
Phoenix