The usual first world problems. Current have the Nikon 24-70 2.8, 70-200 2.8, 50 1.4 and Tamron 90 Macro. Looking to add something on the wider side and torn between the Tamron 15-30, Sigma 20 1.4 Art and Nikon 20 1.8, all of which are outstanding and extremely sharp. Obviously each has pros and cons. Not sure how much landscape stuff I'll do but also not sure if 20 is wide enough. Sigma is offers 1.4, the Nikon is 1.8 is very light but could be an incredible lens for street, Tamron obviously has the flexibility of the zoom but is heavy and larger.
i guess landscapes are nice but I don't know how wide I'd need to go or how much the 15-20 advantage is or whether people who have these use this range often.