It depends. All three protectors will protect against allergens, dust mites, dead skin cells and bodily fluids that can turn into fungus or mold. If you’re looking for 5 sided protection without breaking the bank the Essential is right for you. For hot sleepers that want all the benefits of the Essential with added cooling then the Cooling Protector is what you need. And if you need protection against bed bugs then you’ll need the Full Encasement Protector with PESTLOC zipper.