I've worked for an AV and Security company for over a decade.
AV is about practical balance between security, accessibility, and performance. In other words, high detection rate (security) is not the be all and end all of AV. You have to ensure that CPU utilization is not too high (performance) and that your work is not affected false positive detections (accessibility).
If you want all three,
STAY AWAY FROM FREE AV. Free AV only cares about detection and low cost... they use this as their marketing come-on. But they couldn't care less about performance and accessibility because they have no paying customers to be accountable for. Madalas sila mag false positive. So if you care about your applications and data, and want to prevent data corruption due to false positives,
go for PAID/LEGAL VERSIONS of the big three -- Symantec, Trend Micro, McAfee.
Honestly, the full desktop suites of all three companies have relatively comparable performance. I personally recommend my company's product -- Trend Micro Titanium. Titanium is a version of our product that is specifically designed to run very light and efficient. It wont hog precious CPU resources during recording and rendering. So there, that's my recommendation
