"I know the capabilities of the 24-105 and am wondering if going for the 24-70 without IS on a camera (5D3) that can obviously tolerate higher ISO would be the way to go.I like the reach of the 24-105 and I dig the IS. I am often shooting at 1/15 of a second and the IS is a huge help in those situations, although that is on my 40D and I never go above ISO800 and even then I try to avoid it.Any thou" . . . .