As a slightly off-topic note, are you sure you actually *want* one? When you get back State-side, if you haven't already I'd seriously recommend renting the IS version of the lens for a weekend of shooting to see if you do really like the lens. I was lusting after the f/2.8 IS version of the lens for nearly two years when I first started learning about new things to buy (I'd even have dreams about the lens

) but I rented it for a few shoots and quickly discovered that it was just too bulky and annoying to use, and actually hampered my shooting because it became more of a "status symbol" attached to my camera than a tool.
I've found since then shooting with fast primes has both increased my keeper rates and improved my photography all while saving my back and shoulders some massive discomfort

Of course, YMMV and you might indeed *need* the lens for your shooting situations

Forgot to mention - if you rent the IS lens you can turn it off to see how much you can get away with in terms of acceptable sharpness vs shutter speed... keep in mind the non-IS is a bit lighter so you'd probably be able to get away with 2/3rds of a stop slower than with the IS version (off).
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