Personally, I'd give a miss unless you're very interested in the history of SA.

Soweto used to be a fascinating tour, but now with the giant tourbusses coming through, idk, on my last trip in 2013 (it had been 8+ yrs for me) it felt a bit too touristy and not very authentic.

That said, if you have a spare half day in Josie (which isn't very exciting in its own right) it's a very worthwhile thing to see to get a bit of perspective.