After trying several different toppers (haven’t tried latex yet though), I’ve come to conclude that I like the Ikea Tussoy topper the best. It is a 2", 3.1lb memory foam topper. Starts out rather firm but softens and gives excellent support. Only problem is it sleeps rather hot. Are there any new gel or airflow memory foams that would have a similar feel but remain cool?
Memory foam or gel memory foam in general will tend to sleep warmer than other types of foam materials such as polyfoam and latex but there are many different formulations of memory foam and gel memory foam that are being used in the industry. There is more information and comments about some of the different methods or formulations that can be used to help cool down the tendency of any memory foam to sleep warmer for some people in post #6 here but memory foam manufacturers don’t disclose their specific formulations and there are so many variables involved in temperature regulation other than the memory foam formulation itself that the only way to know whether any memory foam mattress in combination with all the other variables that can affect temperature regulation will be “temperature regulating enough” for you will be based on your own personal experience.
While it’s also not really possible to quantify the sleeping temperature of a mattress (or a mattress/topper combination) for any particular person with any real accuracy because there are so many variables involved including the type of mattress protector and the sheets and bedding that you use (which in many cases can have just as significant an effect on sleeping temperature as the type of foam in a mattress) and on where you are in the “oven to iceberg” range and because there is no standardized testing for temperature regulation with different combinations of materials … there is also more about the many variables that can affect the sleeping temperature of a mattress or sleeping system in post #2 here that can help you choose the types of materials and components that are most likely to keep you in a comfortable temperature range.
In very general terms … the materials, layers, and components of a sleeping system that are closer to your skin will have a bigger effect on airflow, moisture transport, and temperature regulation than materials, layers, and components that are further away from your skin and softer mattresses or foam toppers will tend to be more “insulating” and for some people can sleep warmer than firmer mattresses.
The density of your memory foam topper is also lower than I would normally consider (see the durability guidelines here) although it may be a little less important with a topper than it would be with a similar layer inside a mattress because you can replace the topper without replacing the entire mattress even though you would need to replace it much more frequently than you would if the quality/density and durability of your topper was higher.
If the only issue with a mattress is that it is too firm and there are no soft spots or sagging in the mattress and it’s still in good condition then a good quality topper can be an effective way to add some additional softness, “comfort” and pressure relief to your sleeping system but the only way to know for certain whether a specific mattress/topper combination is a good “match” for you in terms of comfort, firmness, and PPP is based on your own careful testing or personal experience on the combination. If you can’t test the mattress/topper combination in person then there will always be always some risk and uncertainty involved in adding a topper because the specifics of the mattress itself along with your own body type, sleeping position, and preferences can affect which specific topper would be a suitable choice for any specific person on any specific mattress.
There is more information about choosing a topper and a link to the better online sources I’m aware of in post #2 here and the topper guidelines it links to which along with a conversation with a reliable and knowledgeable supplier (that can provide you with good information about how their toppers compare to each other or to other toppers they are familiar with that are available on the market) can help you use your sleeping experience as a reference point and guideline to help you choose the type, thickness, and firmness for a topper that has the least possible risk and the best chance for success. A good exchange/return policy can also reduce the risk of an online topper purchase so I would make sure you are comfortable with the options you have available after a purchase just in case the topper you choose doesn’t turn out as well as you hoped for.