Well, I'm back home, and I'm delighted with the AF-S 58/1.4.
The majority of reviews online have not done it justice, and I'm consequently more impressed than I though I would be.
It's certainly not a un-sharp lens. At least, it's plenty good on my D810 at f/1.4. It certainly has an unusual/unique (for me) focus transition from foreground to background.
Unfortunately, I didn't have much time to focus on taking pics during my stay in Cape Town as it was more about family, however, I have a few images I'll post here from the trip...
One of the very first images I've taken...