Got a used one, and cannot be pleased any better.
I kept going between the f/2.8 and f/4 lenses, until I decided on the f/4 lens.
The primary driver was that the f/4 lens was HALF the weight of the f/2.8 lens. For a senior citizen shooting long high school sports games 4pm to 930pm; JV then Varsity, the lighter weight is very much appreciated by my back and legs.
So the trade-off of 1-stop vs half the weight was worth it.
I REALLY LIKE how light and smooth the zoom ring is. Reminds me of the old 80-200/4.5.
My other zooms have tighter zoom rings, which is more difficult to easily use.
While I expected it, the image quality surprised me.
I am able to crop deep into images where I could not with my other lenses.