I have observed one thing with this type of lens that I have not read about anywhere before on the internet.
The first 24-70 2.8S I got my hands on had a slightly to moderate decentering on the upper left side. The second copy of that lens was slightly decentered on the lower left side. The third copy of that lens was perfectly centered.
I would expect that from older and lower priced lenses, but not from a lens that costs 2400 € and was built in Japan.
