Hi sleepseek,
The Costco site doesn’t list any of the density specs for the Novaform or the foam layers underneath the memory foam layers which makes it impossible to predict how it may feel to any particular individual. Much of the feel of a memory foam mattress depends on all the different layers (not just the memory foam top layer) and how the layers interact together and with the individual body weight and shape. The memory foam layer on the gel mattress however is thinner and it has a “textured” foam underneath it (usually indicating some type of engineering such as convoluted foam or similar) which is typically “softer feeling” than a firmer support foam. The memory foam itself may feel firmer initially but like all memory foam will soften with body heat. This indicates that it may actually “feel” softer than the pure comfort deluxe (which they don’t sell anymore) in actual use but as I mentioned this will depend on the body type and how much you are “going through” the memory foam and feeling the layers underneath it.
Overall … without personally testing a mattress … you are dependent on the descriptions of the layers used to try to get a sense of how it will feel and without this information then the “safest” way to tell how it feels is to actually buy it from an outlet with a great return policy (like Costco). These types of purchases are an “all or nothing” purchase and even the reviews of others can be very misleading because you don’t know how they are “defining” soft and firm and how their own body shape and weight is interacting with the mattress. One person’s soft can be another person’s firm.
What is clear though based on rough calculations of the shipping weight of the gel foam toppers is that the density of the topper is around 4 lb which means that it is mid quality memory foam and certainly won’t last as long as a higher quality memory foam … and of course like all memory foam it will soften over time.
If you are looking for an online purchase of actual higher quality memory foam and a mattress construction that has options and choices that can help “customize” a memory foam mattress to your needs … then this thread may help a bit.
Phoenix