Hi NeedABedASAP14,
Post #89 here has more information about the pros and cons of different types of mattress protectors including the “membrane” type that Rocky Mountain is selling which are a popular choice with memory foam mattresses because they have little effect on the “feel” of the mattress, are waterproof, and don’t interfere with the properties of the memory foam.
I also like that it uses cotton which along with viscose/rayon fabrics would be my preference over synthetic polyester fabrics laminated to the membrane.
Phoenix