I like Opera, though I haven't tried FireFox. I started using Opera back before Mozilla/FireFox was so popular, and I'm very happy with it, so I see no reason to switch.
IE is all right... I don't hate it as much as some people do. I've never had real problems with it, and I still use it occasionally for testing stuff.
One main reason I don't use IE is because it lacks many features that are necessary for "power users" like me. I suppose something like Avant could add those features, but I've never tried that either.
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