AVG or Avira?

ive been using norton internet security ever since, it was installed for free when my dad bought me the laptop. however, it expired after a year, so i thought of using free anti-virus like AVG or Avira. but the question is, which is better between the two? Ive been using AVG for sometime unfortunately, my computer crashed because of the so called "brontok worm". After that incident, i switched to avira. it detects and beeps when worms, phising, viruses, spam, adware and malware secretly jumps into the pc. I find this amusing since the AVG cannot detect all these(no offense to AVG users). As far as i know, AVG is often downloaded in cnet downloads. but using AVG, it always prompts you to scan your pc manually to be able to detect such threats. Although avira updates slow(depends on isp), you can be sure your pc is secured and protected using it.

See also:

macbook air vs. lenovo thinkpad x300