I've seen AV software work successfully Far Far too many times (over the years) to consider not using any.
- and I am also one of those super careful people.
- - but sometimes have to work on files from other trusted people (who do not use AV software >_< )
and a decent number of files are Extremely destructive (a couple I have seen on friends PCs
- sometimes in your face obvious destroying all your jpg and avi files for eg
- other times slowly progressively destroying you PC's core files over may months gradually corrupting all files on your PC so by the time you notice critical damage is done (and to a large proportion of your backups too :s )
Anyone working as an IT Admin in a largish company 200+ people will Know you don't want to run with no AV lol
(most viruses come from the semi PC savvy Directors and upper managers then infect everyone else PC's over the internal network if the AV does not stop it in time)
Not running AV and not seeing a problem does not mean you are not infected by a nasty virus either
- I have had viruses try to infect my PC from sites I trust like Tomshardware through their advertisers more than once before.
- trusted downloads from original website sources of programs have been infected before a few times in my personal experience, though this is very rare.
Basically you would be Crazy to run a PC with no AV, unless you are perm offline and never accept files from 3rd parties (not really possible unless you never install any software on your PC)