So Which Is Best?
Avira is the technical standout. It has posted excellent scores in recent protection tests and it also ran away from the competition in our performance metrics. The downside is a confusing user interface. I had to explore the software for a few minutes before I understood how to operate it. If Avira could make the software just at tad more intuitive it would have the perfect product.
Avast! may be a better option for users who want to fuss with protection as little as possible. It is nearly as good as Avira in our performance benchmarks and it offers a slick, simple interface. Advertising is kept to a minimum, as well.
Lavasoft and AVG are suitable choices, but both have a catch that may be significant for some users. Lavasoft uses far more resources than the competitors while running in the background and AVG has an unattractive interface loaded with advertisements for the full version and other AVG products. Both offer competent protection, however.
Last, and least, is Microsoft Security Essentials. It was not the slowest in our tests, nor did it eat the most RAM, but protection studies have shown it to be the least effective at stopping threats by a large margin. Missing 5% of recent threats in the AV-Test roundup doesn't sound like much, but all other competitors missed 2% or less. Going with MSE makes you substantially more vulnerable.
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