Quick update - I received my lens last week and so far I'm very happy with it. Autofocus is snappy and accurate and colors seem to be reproduced more vividly than any of my other lenses. I did go ahead and order the dock also, and it arrived yesterday. It turns out that my lens shipped with the latest firmware version, so there was no update available. I really wasn't that surprised, because I thought the AF was already pretty fast, I couldn't imagine it getting 50% faster (but I hoped anyway).
I haven't messed with the AF microadjust settings yet. It doesn't seem to be terribly out of whack at the moment, but I'll take some sample shots soon to make sure.
I tried out the dynamic OS and speed-priority and focus-priority settings briefly yesterday. It's been raining here in Texas so I didn't get much time to try them out, but my first impression was they didn't seem to make too much of a noticeable difference to me. Maybe time will change that. We should have some sun on Saturday so I plan to take it out and shoot most of the day. I have C1 set to dynamic OS and speed priority, and C2 set to dynamic OS and focus priority, so I can play around with them and see what suits me best.
In the meantime, here's a shot I managed to get last weekend shooting the house finches in my backyard.
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