Windows 7 without anti-virus software

Just a quick question I thought I'd ask...

Would you say Windows 7 is safe to use without anti-virus software ? I dual boot my laptop with Windows 7 & 8. My Windows 8 has Norton installed but I only bought the license for one computer, as I didn't anticipate I'd want to dual boot in the future.

I know it's down to the browser a lot as well, so I'll tell you that I use Google Chrome and won't be switching anytime soon.

Also, I don't visit any relatively dodgy sites, only ones that are widely trusted.

Leave you answers and personal experiences below.