I was not sure whether this topper would be thick enough:
After doing research, the 1" seemed way too thin and the 3" was too expensive... So I went with the 2". It is the perfect size, fits well under all my fitted sheets, does not slip around, and does not smell beyond the first day or two.
it is supremely comfortable. Also, it seems to absorb a lot of the movement of a partner fidgeting or rolling around.
Definitely go with this one, especially if you want to spend a moderate, not a hefty, amount of cash on it.
*Though it doesn't come with a cover (we just use a mattress protector over it).
*maybe for super-heavy people, this would not be adequate... but I think for most people it is great.