Still testing the waters with that 100-500mm. The weather's been decidedly uncooperative as far as having decent light for such a lens, meaning I have to crank my ISO and swing the post processing bat a bit harder than I'd normally like to.
That said, this was handheld, f/11 if I remember right, and 'only' 1/400 at ISO6400, so I can't gripe too much for what its giving me.
I do get some mild CA, but that was kind of expected. The lens absolutely shines for 'close' photography though, which while it wasn't why I bought it definitely makes it worth keeping.