70mm: IS beats L here. The difference is clearly visible, L can't match IS output in therms of sharpness.
100mm: IS is still better and sharper than L at the same apertures.
135mm: Wide open and @ f5.6 the IS is sharper than L. At f8 the result are almost identical, no big difference.
200mm: The only setting, where L beats IS in this corner. Both are similar soft wide open. L is getting sharper when stopped down, while IS remains relatively blurry at any aperture.