-18-200 for Canon: ok
-17-70 for Canon: ok
-50-150 for Canon: minimal frontfocus (but unusable at f2.8 in the 100-150 range on close focusing distance (headshots etc) - because of the shallow DOF, where frontfocus is more visible, image is unusable)
-10-20 for Canon: ok
-70 2.8 macro for Nikon: ok
-300 2.8 for Canon: frontfocus
-8 mm f3.5 circular fisheye for Canon: ok
-30 1.4 for Canon: weird AF issues (read the complete review for details, posted a week ago)
-70-200 2.8 Macro for Canon: frontfocus
It's really a shame that 70-200 2.8 Macro has frontfocus issues, because it's tack sharp at f3.2 (very few Sigma's are). Here are a couple of samples which came out ok (tested on Canon 350D):
f3.5. 1/500, ISO 200
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100% crop from the photo above
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f3.2
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And this is the focus test. I focused on the line below number 50. Frontfocus is quite pronounced (f2.8, 200 mm):
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