Thanks! There is a lot of confusion coupled with cognitive dissonance preventing people from accepting the truth behind testing, laws of physics and common sense reasoning. Add to that the notion that somehow it is not possible to outdo a Nikkor lens on a Nikon camera - and that's how so many 200-500 mm lenses get sold. I much prefer using my Sigma Sport to anything other than my 600mmF4, other than those times when I can use a lower ISO/faster shutter in crappy light, and don't mind carrying an extra 6 lbs of tripod and head.

That being said, I took my Sport out late last month and got this image, hand-held, in less than ideal light. It's a portrait crop from a landscape image, so it's about 17 mp or a little less than 50% of the original image area:

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