Whether this lens would be useful for portraits wide open remain to be seen. I know the 50/1.2 really does magical busts wide open, but can't say I'm ever concerned with sharp ears. Unless I'm at f/1.2 for the magic, I skip straight to f/2. Anyhow, f/1.2 could be useful on a 35mm for those times when I am struggling to get as much separation as possible, though I need to flesh out my available focal lengths more before I'm shopping for a 35mm. I think we can all agree that 1.2/1.4 and even 1.8 are all good enough when it comes to low light with modern sensors. The question is will this lens bring some kind of magic wide open. None of the shots I saw showed any, but I also know someone could take hundreds of shots with my beloved 50/1.2 and fail to demonstrate it's magic as well.
Regardless of this lenses quality, I hope it sells well. If the likes of Samyang, Irix and DZOptics are successful then we will likely see more manual primes popping up. Which I am happy about. We are bound to get a gem at some point if they keep popping up . . . I hope.