Louie - I picked up a 1.4III because I'd read folks posting that it was a tad sharper with E lenses. So I have both the 1.4II and the 1.4III. To be honest, I can not see a real-world appreciable difference in image quality between the two. Maybe I'm just not picky enough, but then again I don't spend hours going over a single image at 100% working and reworking the processing.
I have not compared the difference in AF speed between the two, but then again when used on my 600e, I didn't notice any difference that stood out.
I have not compared the difference in AF speed between the two, but then again when used on my 600e, I didn't notice any difference that stood out.