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Honestly: code it all up in just one standards compliant browser (so dump IE, yes: the one your visitors use)
Once it works in one of those browsers, check it in the other standards compliant browsers: in 99% of the cases there's not one thing you need differently.
After that, your page is done (yes untested in IE, hold on).
Now you work around the bugs in in the different versions of IE using a conditional comment.
That way you only need one browser at a time and won't need to check it at every iteration in every browser.
As an added bonus: it helps you not go insane over the different versions of IE.