I've used the Canon equivalent (the 70-200/2.8IS) for awhile. I've shot portraits with it. Also weddings and netball. It's a great lens (although it's very heavy).
On a Canon body that is. Don't get me wrong, this lens is great on Sony mirrorless bodies with the Metabones adapter, but there are a few issues. Eye focus doesn't work well, and this combination is problematic when trying to focus in difficult lighting. And this happens a lot at weddings.
Because I can't afford to miss a critical moment due to focussing issues, I've decided to purchase the Sony equivalent- the 70-200/2.8 GM. It's not cheap, but it's native Sony lens, so it should do better. There's only one way to find out- and I'll find out soon.
Here is a video outlining my reasons for buying a duplicate lens from a different manufacturer:
Let's see how much a difference this lens makes.
More updates to follow,
D