I have been using this dev for a couple of months, I really like it. It's next to impervious to temperature ("around 20C" is enough) !
I do presoak the film; it's not recommended in the article, but with the dyes in films poluting the 2 baths, they become dreadful very quickly; the presoak gets rid of most of the dyes.

Sheet film doesn't seem to need agitation in B, but 120 film /in steel tank/ do need an inversion every minute or so, otherwise the film doesn't seem to clear properly (fog in the middle). I've seen reports saying that Paterson tanks do not exhibit the problem.

Otherwise it delivers exactly as promised, nice fine grain, and a really great range of tones, most especialy in high contrast scenes...