I used the 55mm f1.2 for many years and then bought the Noct. I'm happy to have a lens that should keep rising in value but I'm noticing that I can't really see a difference in quality between the two lenses. The Noct is a bit sharper wide open but probably not $3k sharper. I've heard there's a hand-ground element in the Noct that keeps it's price high. Curious to hear from others who own the 58mm f1.2.