That's not what I meant...
The 24-105 that you listed as example with IS
practically trails the old Sigma 24-70 in all areas (from distortion, vignetting to CA), and not just sharpness:
They need to do better than this with their new lens (IS just makes it harder) - Theses points are already well taken in others Nikon forums
-> Sony got it right... their optical path is the simplest (i.e. no IS)