We have VIPRE running on over 200 machine and needless to say we have had some problems at times mainly with the single core processors. This seems to be better than it was over the past couple years. Everyone has their own opinion, but we are basing our opinion on the facts in a real production environment. Avast is too bulky and a memory hog, we needed something fast and a small footprint. Make your own choice, business environments need the protection!