Hi anotherscott,
You’d want to analyze the products based upon specifications, using the durability guidelines here. Pros/cons or better/worse would be personal and part of your own personal value equation.
Regarding the Helix, I have talked with the 3 founders of Helix Sleep and they consulted with a well known group of PHD’s and researchers in sleep ergonomics and have designed a rather unique mattress that uses a customizable combination of 3 different comfort/transition layers. They use a questionnaire with their customers that takes information such as BMI, body measurements, and sleeping positions into account and use an algorithm to choose the both the order and the firmness of each of the comfort layers that are most suitable for each of their customers. The 3 comfort layers are on top of 4" of 1.8 lb polyfoam with two different firmness levels. They can also build a side to side split with different combinations and firmness levels on each side of the mattress for couples with different needs and preferences. They use good quality materials that would be suitable for most weight ranges in terms of durability but I would add a slight caution for higher weight ranges (more than about the lower 200’s or so).
Comfort Layers:
2" Helix Dynamic Foam (HD polyfoam) in one of three different firmness levels (2.5 – 3.0 lb.),
2.4" microcoil,
2.0" 1.8 lb polyfoam in one of three different firmness levels. The firmness of the polyfoam and the order of the comfort layers is customized for each person
Support Layers:
4.0" 1.8 lb polyfoam
Regarding the Luxi, they apparently changed their design in May and I have inquired but have yet to receive back true confirmation of their specifications, and have received conflicting and sometimes incorrect information from them via their customer service representatives. They are still listing their old specifications online, and until the information can be confirmed accurately as to what is inside of their mattress, I would advise a strong caution if considering this product.
The specifications I’ve been provided are different than what you listed in order, and I have no confirmation on the densities of the materials, so I will not list them.
1" Quilt/Cover Layer
3.5" SBT Layer
1.5" Transition Layer
1.5" Luxitex Layer
3.5" Base Layer 3.5"
Unless they’ve changed their design, the SBT, transition and Luxitex layer are laminated together in a single piece, and this can be rearranged with the base foam piece and can also be flipped to provide four different levels of comfort.
The pod design of the Luxi using the SBT foam piece would be different from the more traditional solid pieces of foams used in a mattress, but whether or not you preferred this could only be determined through your own personal testing, not the advice presented by other people (see post #13 here).
Phoenix