I tested Avira AntiVir 8 last night (the free version) and it blocked (quarantined) 5 out 5 pieces of malware. Perfection! 3 pieces of malware were detected via Avira’s signature engine and 2 others were blocked via the Avira heuristics engine (very nice for a free app btw). 
Here are facts:
- 5 Malicious URL’s tested.
- 5 Malicious URL’s were prevented from infecting the host computer
- Internet Explorer was used.
- PC was clean
- Avira AntiVir Free version 8 was used
- Signature DB was updated minutes before test
- Heuristics were set to high
Watch the prevention review below:
httpv://www.youtube.com/watch?v=0_eDef2r5is