How confident are you in your u4/3 kit?

Capping the ISO like that is an easy thing to do in just about any lighting situation as long as you've got the fast glass to cover yourself when light levels drop. Last year in Paris I was just fine with the dated 12MP sensor of the E-P3 down in the existing murk of the Catacombs and often very low lit chateaus because I was using the 12mm f2, 25mm f1.4 and 45mm f1.8. As long as you have the glass to cover yourself in any situation you might be shooting in, with the exception of high-speed sports, the Micro Four-Thirds system should be able to handle it.

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"There's shadows in life, baby.." Jack Horner- Boogie Nights