Both Serene and Aerus have been discussed previously here on the forum, and to make it easier, I just copied over some information about each that you may find helpful:
[i]Serene foam is one of the "newer’ generation of high-performance polyfoams, which are of a higher density and good at pressure point relief, but do not have any of the viscous properties (it is not a memory foam). It is also not a latex foam. Carpenter introduced Serene in 2015 and re-launched it in 2016. It is generally a higher density (2.5 lbs as an example) and it is CertiPUR-US certified. This generally would be a good quality and durable plush material. It is not technically a high-resilience foam, as that would require a 2.5 density or above, along with a compression modulus of 2.4 or above.
High performance polyfoams such as this are becoming a bit more popular, some to offer the conformation and point elasticity found in memory foam, but to be more open-cell and breathable, faster in recovery, and not so temperature dependent. Others are designed to be closer to latex in their characteristics. And then some are simply designed to be more durable versions of low-density polyfoams.
These foams are usually located in the uppermost layers of a mattress to take advantage of their point elasticity, and are sometimes offered as a topper. The overall feel of any mattress is of course dependent upon all of the layers within a mattress, and the “deeper down” these foams are placed within a mattress (even beneath a thicker covering), the less noticeable their softness will be.
The Aerus Plus memory foam at 5 lb would be a good quality memory foam, but memory foam itself is not a “supportive” material, but instead relies upon the firmer and more resilient foam layers and components placed beneath it to provide deep support and assist with maintaining a more neutral alignment. [/i]
Both these foams would generally be quite plush (in lower IFD ranges). The more important thing to know would be the density, and in this case both would be considered to be better quality materials.
Being a softer material you will tend to “feel through” to the deeper layers, so this doesn’t necessarily mean that the material is a lower quality. This is more of a reflection upon the plushness and compression modulus of the foam.