Before we are going to our main point, 2 memory foam mattress toppers pros and cons, let me give you the definition of memory foam firstly. The memory foam is derived from polyurethane and some chemicals thing in order to get proper density. The technical name of memory foam is visco-elastic polyurethane foam. For your information, this kind of mattress has millions shapes of spherical. So, we cannot imagine how these spherical are able to be foam inside of mattress. Most people love this thing because it has controlled weight and temperature by themselves.
The 2 memory foam mattress toppers have good longevity. Many people think the memory foam is easy to be torn and moldy because of dew or moisture. One memory foam mattress is able to carry three or four years of durability. Of course double toppers will last around these years too based on your bedroom environments. For 4.0 lbs or more density will have longer age rather than lower density such as 3.0 lbs. The old toppers will lose their softness and resiliency. Thus, you will not get comfortable toppers anymore if more than four years. I think this durability is quite good because you have capability to spend your money once in four years.
I believe 2 memory foam mattress toppers bring pros and cons for its users. The disadvantage of double mattress may be ignored by them because it gives more thickness or depth on the bed. However, it will cost your money. You just simply buy one topper with high thickness like 8 inches or 12 inches. It is more affordable than you buy double toppers. Another disadvantage is about the unconsciousness of sleep which usually brings us into the edge of toppers and usually falling down from the bed. So, double toppers will give higher impact of this accident.
It will be unreliable if I did not talk about the benefits of 2 memory foam mattress toppers. Of course, the thickness is the real benefits in this point because you will have very thick toppers. It gives some comfortable feel when you are sleeping on them. Moreover, the warranty coverage is also longer than single topper. The memory foam gives softness surface on your body and the durability is also double around eight and ten years of longevity. The thickness is also bringing romantic scene because both of you are in higher place with 2 toppers.