I always wanted a 500 or 600 but as I age I'm not so sure now. My sites are now set on a 400 DO II. With a 2X TC you get AF and I have seen some very nice results. If all goes well I may have one this time next year.
The DO II is... AWESOME. I miss that lens a LOT. Reading people's reviews and comments, you'll come across stuff like:
"weird specular bokeh" and
"it isn't as sharp as the 500/600/800", and
"not sure how well it works with TCs"
Seriously, don't even listen to that stuff, the lens is 100% amazing. And the size is utterly charming (it's shorter than the 100-400 at 400mm). It works perfectly with the 1.4xIII, and really great with the 2xIII. I'll probably end up going back to it here in the near future myself.









I'm lucky to have gotten the few that were barely decent. The rig is MFA'd, my SS is high enough, hand shake shouldn't be an issue, the light was fantastic (which makes me even more depressed). I may send this 100-400 to Canon.

