Sigma's own MTF looks better than the one of their 50/1.4 Art. And they claim it has close to no coma. It certainly is an interesting lens. Although not easy to justify in between the 35 and 50 mm.
As for the Nikon prices: to me they play the "at this price it has to be very good" game. Except for the 500 PF which is nearly "cheap" compared to their other offerings.
As for the Nikon prices: to me they play the "at this price it has to be very good" game. Except for the 500 PF which is nearly "cheap" compared to their other offerings.