I would consider
www.lensrentals.com. They should have a copy of each lens you are considering. Great way to find which you prefer and sometimes they are willing to sell the particular lens.
As for the 1.4's. I have the Sigma 35 1.4 and love it. I like the fact that Sigma still designs a lens with the idea of possibly using it manually. Nikon IMO has long given that up. Their fast wides have great AF, but there is no good feedback with when you attempt to manually focus. Examples, 20mm 1.8, 24mm 1.4 both of which I owned, but sold for the Sigma alternative.
The only issue I have had with Sigma is Quality control. There does seem to be quite a bit of sample variation. I tried 2 35mm's and found the 2nd one the best. It took 3 24mm 1.4's as the first two were off centered. The 20mm 1.4 I just received and it seems fine.
One other facet, all of these lenses will suffer from coma, if are planning any astro work, sadly the Sigma 24mm 1.4 is one of the worst in this regard. The Sigma 35mm has a very good coma correction however. The Samyang 24mm 1.4 is the best I have used for coma, but it's manual only and there are times I want AF. Still a great lens for the dollars, about the same size as the Sigma, but 1/3 less weight.
My use is landscape, on Nikon D750 or D810.
Paul C