There is a lot of speculation that a memory foam mattress will get hot while sleeping on one. This can be true is some instances if the memory foam is made from closed celled memory foam, usually these are made in the far east using cheap memory foam. Most quality memory foam mattresses are made using open celled memory foam, that allow good circulation of air. Also a good quality memory foam will have air flow channels which will help to allow air to have excellent airflow all around. Also a coolmax or outlast cover will also aid in keeping you cooler in summer. Overall a good quality memory foam mattress will be made with the above following features and will not be any warmer than a normal conventional made mattress, if anything they should feel cooler.
For more information please look at www.memory-mattress.co.uk