This is identical to me. Love Opera but use Chrome as a secondary browser or for when something doesn't work in Opera.
I also install LastPass and XMarks in each browser as well.
Thought xmarks was going....
They were taken over by the people who do Lastpass
Ohh and of course, I use FF4 because of the Overclockers UK extension...shameless plug there of course as I'm the maintainer!
https://addons.mozilla.org/en-US/firefox/addon/overclockers-forum-menu/
I still use ie 6 It loads so much faster than all the modern ones and I like being able to switch between IE and Windows Explorer in the same window (I have certain directories bookmarked). I take various measures to help security, as I know it's not as strong as FF etc and seem to do ok - I've only had one or two malware come through in the past 3 years or so.
Still, it could do with tabs. Is there a tabbed IE6 clone out there with more modern security?