i would highly recommend updating to IE10, since Microsoft finally fixed all the bugs with it about 5 months ago, i already upgraded to IE11 the other night, but i think i am rolling back to IE10 since there are still a lot of bugs in IE11, i also have Google Chrome set as my default browser
For me IE9 was rock stable...i went to IE10 for its functionalities but bumped onto troubleshoots with it too often. I'm now with IE11 for the same reason and at the moment encountering no serious issues.
I'm one that using only one browser.
But if you intend to use another browser and time to time browsing with Internet Explorer i'll tend to tell you, stick with IE9.
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