Sophos is a well known anti-virus vendor. Kaspersky is too.
However, choosing an anti-virus is a matter of personal preference, your technical ability and experience, features offered, the amount of resources utilized, how it may affect system performance and what will work best for your system. Other factors to consider include effectiveness, user friendliness, ease of updating, ease of installation and removal. A particular anti-virus that works well for one person may not work as well for another. You may need to experiment and find the one most suitable for your use and your system. There is no universal "one size fits all" solution
that works for everyone. Another factor to consider is whether you want to use a paid for
product or free alternative
. For more specific information to consider, please read Choosing Your Anti-virus Software
.No single product is 100% foolproof
and can prevent, detect and remove all threats at any given time. Just because one anti-virus detected threats that another missed, does not mean its more effective. The security community is in a constant state of change as new infections appear. Each vendor has its own definition of what constitutes malware and scanning your computer using different criteria will yield different results. The fact that each program has its own definition files means that some malware may be picked up by one that could be missed by another. Thus, a multi-layered defense using several anti-spyware products (including an effective firewall) to supplement your anti-virus combined with common sense
, safe computing
and safe surfing habits
provides the most complete protection.