Hi Allianna,
If both of them use high quality and durable materials then the choice between them would be a preference choice not a “better/worse” choice. There is more about the differences between a latex support core and an innerspring support core in post #28 here but you are really the only one that can know your own preferences.
If they are a Serta iSeries then they would be made by a Serta factory and if you can’t find out the specifics of the materials inside it I would avoid it completely. “Blind” mattress purchases are much too risky in spite of what the salespeople that sell them will tell you. The iSeries hasn’t been out for long enough for anyone (including the salespeople that sell them) to be able to tell you anything meaningful based on personal long term experience and Serta changes their mattress designs on a fairly regular basis as well so by the time a specific mattress has been slept on by enough people for long enough to have some meaningful durability feedback it would no longer be available anyway.
You can read more about the Serta iSeries Vantage in post #2 here and as you can see I would avoid it.
Since you are also looking at memory foam there is more about the pros and cons of latex vs memory foam in post #2 here.
I would always keep in mind that no matter how a mattress feels in a showroom or how well you may sleep on it when it is new … if the materials soften or break down much too quickly relative to the price you paid and you lose the comfort and support that was the reason you purchased it and need to buy a new mattress much too quickly after only a few years then it would have little value compared to a mattress that used much higher quality materials that you can reasonably expect to sleep well on for much longer.
The link I posted previously has more information about the different ways that one mattress can “match” or “approximate” another one. If you are looking something that is “comparable” in terms of comfort and PPP based only on specs then you would need to know all the quality and comfort specs of both mattresses and even if you were able to find this out it’s very unlikely that you will find two mattresses with an identical design or identical materials so the only way to know how a mattress compares to another one in terms of comfort and PPP will be based on your own personal testing or experience. In very general terms … the iSeries mattresses have a pocket coil with foam layers above them that always include at least some memory foam and have a mix of other types of foam as well depending on the specific model.
If you are looking for something comparable in terms of quality and durability then you would need to know the type and quality of the materials in both mattresses so you can compare the durability of the materials inside them but this will have little to do with how it “feels”. Since the iComfort mattress uses some very low quality materials it certainly wouldn’t be difficult to find many mattresses that used more durable materials.
There are always 3 parts to choosing the best possible mattress which are …
- Testing for suitability and PPP (or if you order a mattress that you haven’t tested in person making sure that you have a good exchange/return options)
- Checking the materials inside it for quality and durability to make sure there are no weak links
- Comparing your finalists for “value” based on all the other parts of your personal value equation that are most important to you.
All three of these are important in choosing a mattress that is suitable, durable, and is the best value choice for you.
Phoenix