Upload & Sell: On
Sad news update. . . Upon further testing, the lens has focusing irregularity on both my 1Ds3 and 1D3 bodies. By that I mean erratic front and back focusing on the same body while trying to get MA'ed. It did better on the 5D2, so it may be a firmware issue. (All shots wide open, still subjects at ranges between 2 to 75 feet, center point AF in One Shot.) Both the Mk III's have been to Canon within two months and had their focusing serviced and firmware upgraded. The new lens(es) may work better on newer bodies in the Digic 4 and 5 versions -- just a speculation on my part.
Otherwise the lens is a significant improvement over the original -- much better CA and low distortion, super-quiet in comparison, great color and tonal rendition, fast AF (plus IS, of course!). I'm not badmouthing the unit, its just my experience on these bodies.
Just to make absolutely sure, I mounted my original 28mm and shot the same subjects with both Mk III cameras -- almost 100% accuracy in the AF (although it seems super-loud now with its ARC drive!). So, I've withdrawn the old 28 from sale on B&S, and gotten a return merch form from Adorama -- great customer service, BTW.
You know the old saying, "Nothing ventured, nothing gained".
I'm still looking forward to the 35/2 IS a little later on. Perhaps I'll have a 5D3 or 6D by then.
Thanks for the opportunity, Adorama!