Opera...It just works. There are some bugs but speed dial and multiple session saves keeps me coming back.
Use Chrome for compatibility issues with Opera on some sites and the sheer speed of it.
Explorer for Windows updates

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Firefox not used. It's nice but too tweakable for me. I get in and cannot stop until it's so secure that most sites I visit require me to allow the access manually and that's now ideal for my surfing. I know it's good but its like tweaking windows...blah blah blah.
Sooo Opera.