Kaspersky Anti-Virus and McAfee AntiVirus are both well known and have a loyal user-base. The feature set is not too different from Norton’s. Kaspersky offers a 3-user license but this has been a cause of problems for some with license validation expiring periodically. McAfee’s product performs scans slower and seems to drain more resources but those that are familiar with the product prefer to stay with what is familiar.
Overall, choosing between free virus removal software versus purchased software is not so much about features as it is about what you are comfortable using. Customers who have used Norton for years would not want to switch unless they changed their interface making the software harder to use. The same applies to Kaspersky and McAfee. The difference is usually whether you are already familiar with a package. If antivirus packages are new to you, then several offer a free trial period and you can see which fits best.
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