You must obviously know that by visiting web pages alone you can get viruses without downloading at all.
If you're using an up to date, secure browser then this shouldn't be possible. This was a huge issue back in the days of IE6 but it's been a long time since I've heard a case of this happening (with an individual using an up to date, modern browser.) Things are a lot more secure nowadays and this really isn't too much of an issue anymore.
Without going in the technical side of things yes you are correct you can possibly be safe as you suggest but one thing you must not assume is that most people on this forum probably lack the knowledge and skills to avoid getting viruses and you must admit you are taking a big risk, no matter how good you are.
It is highly recommended you should use a security suit as you are exposed to the risks when surfing the net.
To everone, If you want to risk it go ahead but dont complain when you get a good infection that stuffs your PC up.
Geez, you make it sound like you could be blown up just by surfing to a dodgy website! No, I don't agree that I'm taking a big risk in the slightest. I'd actually flip that one on its head and say if you're in the position where you're taking no backups and as such if something happened to your PC it'd be disastrous - THAT'S the big risk situation. None of my data is actually stored on my windows box at all and it's all backed up frequently - so at the end of the day if a virus does trash the box I just need a couple of hours to reinstall windows, programs and get everything back up and running again. If my windows box was mission critical, couldn't be restored easily and / or stored lots of my data then things would most likely be different.
And of course, antivirus software is not sufficient in its own right. If you're still stupid about what you let through and run then it's not going to do anything at all - security is only as good as its weakest link!
Sure, running antivirus software is a good idea in a lot of situations I agree. But at the same time there's a lot of people that choose to run without it and are perfectly sensible for doing so. As long as your reasoning is well backed up and not along the lines of "I can't be bothered", chances are you're fine without.