It was supposedly replaced by the UPS 15-42, also 3 speed
But the old 20-42 speed one had a very nice low flow curve (as I read it), perfect for my basement 28ft 3/4" Slantfin run (out of 80ft total basement zone run).
I figure that run is about 5ft of head--20-42 would give 2gpm vs 5gpm by 15-42 or superbrute 15-58. I have an old recently disconnected 20-42 from the family house that I'm thinking of installing at my place just to hold me a few years until I can replace my old boiler. Currently installed is a B&G LR20BF 'Little Rooster' which is way overpumping at 13gpm or so--sounds like an oil well just before it gushes.
Glad that when I do get a new boiler, the new Wilo micro circs will be available.