I have the 50 1.2, and it's a little beast. Stopped down it performs like any other nikon 50, sharp as hell and smooth OOF. At 1.2 or 1.4, the OOF gets a little obtrusive and bubbly, but it's a style, not perfection. It's a fun look when you want it. Great lens for fashion, if you have lights in the background.
You pay a little for the 1.2, and a lot for the personality. I still prefer walking around with a 1.4, if only just because I baby the crap out of the 1.2.
(note, this doesn't necessarily apply to the noct, which IIRC was mainly marketed for astrophotography and scientific optics, according to Mir.)