I think in truly ideal circumstances the old 400 is probably a wee bit sharper, but the 200-500 is much easier to use and can get close even hand held. And, of course, there is a little post processing one could do that would likely make the difference appear even less in an actual print or posting. Both the images above were cropped in Irfanview, which doesn't do quite as good a crop as View NX-2. I think the Nikon program gets better definition from crops, perhaps because it either crops before converting to JPG, or converts a little better.
My sample of the 200-500 was bought new from an actual store, so I was able to test it on site. It's one of the first batch (6006xxx serial number). When I first tried it, it had just come out. I tested it on a D3200, and the focus issue for which it was soon recalled occurred, so I gave it a miss. A few months later I was back at the store, and there it still was. I asked if it had had the recall, and it had. So I bought it then, figuring it had been pretty well gone over. I think it's a pretty good sample, and have been generally pleased with it.