Looks pretty good to me. I would be more than happy with that
performance.
My Mom and Pop dealer got one from Canon to demo the other day
during their anniversary sale. I took the same comparison shots
(wide open) at a store across the street vs. my 70-200 f/2.8L IS.
70mm at f4.5 - 70-200 sightly sharper
100mm at f5 - 70-200 sightly sharper
135mm at f5 - 70-200 sightly sharper
200mm at f5.6 - 70-200 sightly sharper
300mm at 5.6 - 70-200 + 1.4 mkII sightly sharper
Image quality was a touch soft, but with simple sharpening - match
up very well with my 70-200 shots.
Built quality - very light, very small. Only complaint: the zoom
ring, it had a little too much movement in the 70 end.
A little pricey, but I ordered one. Why: small and light, hardly
noticeable, walkaround day lense with my Lowepro off-trail 2 and
28-70 f2.8. I will stick to my 70-200 for low light/indoor
shooting. Also the image quality sold me. I expected it to be
softer than what came out, but this is really a outdoor lense.