Can the high price be a con too? I did write this as a con and I would leave it if the stabilization was the only difference between the 70-200 f/4L IS and its predecessor. But there is more! The picture resolution is a bit better and the bright light performance is better.
great picture quality in the center and at the edges of the frame, well controlled chromatic aberration, almost absent coma and astigmatism, very small vignetting, small astigmatism, fast, quiet and efficient autofocus, very solid build, high quality build, efficient stabilization
if we try hard to find some flaws, we might say that the performance for f/4.0 and at 70 mm focal length could be a bit better