ISO 400 is sort of my tipping-point sensitivity; to shoot action outdoors, I generally have to bump up the setting to at least ISO 400 in order to reach a sufficient shutter speed. And because few consumer cameras are fast enough at shooting burst raw+JPEG, the in-camera JPEG processing has to be decent as well. The T3i fared pretty well under these conditions. There's some color noise in the brown fur and some mushiness in the details, but both are typical in this class. Overall, I consider this good enough to use, but still wish I would have been able to shoot raw to clean it up.
(1/125 sec, f7.1, spot meter, AWB, ISO 400, 18-55mm IS II lens at 55mm)