I was pretty sure that the Sony a99 would do low light pretty darn well. Here's stage shot at the Austin City Limits stage. I'm shooting from in front of the stage. The color balance was set to auto. Lots of colored lights and the front lights were tungsten. I was amazed at the dead on skin tones. Hand held. 1/160th of a second at f2.8 @ ISO 6400. Still pretty sharp at 4000 by 6000.
Tamron 28-75mm f2.8 lens. Shot as a Jpeg.