@soaringturkeys — I was skeptical about ISO 160, but here is the result of my quick test with a Canon: http://cameraclicker.com/Compare/MoreNoise2/Noise_5D_Mk_III.htm
I was surprised by the result! I think ISO 160 and ISO 200 look about the same. I think ISO 500 looks better than ISO 400!
Thanks for pointing that out. As time permits I will test my other bodies to see how they perform.