Well, long time ago I used to try a hell lot of AntiVirus products but now I stopped it.
My experience was F-secure was terrible. It was bloaty, crap and missed out several viruses in my system.
Kaspersky is hell lot better than F-secure.
Though I'm still waiting for the newer version of NOD32. NOD32 2.7 was the best AntiVirus, but NOD32 3.0 was a disaster. An year back, NOD32 2.7 + Comodo Firewall + Windows Defender used to be my combination but now its Kaspersky.