Hi gumball,
The choice between different types of materials or mattresses is a preference choice rather than a “better/worse” choice so you are really the only one that can decide which one you would like more. There is more about the differences between latex and memory foam in post #2 here but the best way to know which one you would tend to prefer would be based on some local testing on a range of different latex and memory foam mattresses in different firmness levels.
Phoenix