I really love that this mattress cover completely encompasses the mattress. I have allergies and have had pneumonia before, and I was instructed by my doctor to get an allergy protection mattress cover and pillowcase covers, so it brings me great comfort to know that the mattress is truly free from allergens. My one issue with this cover is that it is incredibly difficult to put a mattress topper over it securely and without it bunching up because it is not completely taut around the mattress.