I have sinned. Spent money that should have been used for food, rent and other unexpected expenses to buy a nice second hand F6. For me, it has been the ultimate camera since it was launched back in 2004, but apart from that, finding sensible reasons to buy one hasn't been easy. It still isn't, but I did anyway.
I will mainly use it with AF lenses (I have a rather complete OM setup for when I want to go all manual), and will mainly carry 3 primes. I already have a 50 and an 85, both f/1.8. What I need now is a WA lens in the 20-28mm range. The f/1.4s are out of the question due to high price, so the main candidates are the Nikkor 20, 24 and 28mm f/2.8. They have gotten somewhat mixed reviews on digital cameras, but it's my understanding that they all work better with film.
That leaves me with the question: Apart from the obvious difference in focal length, which of those lenses will give me the best results on film. I'm not too worried about bokeh when it comes to WA lenses, but sharpness, preferably corner to corner, is of great importance.
There are obviously outsiders that I may consider as well. The Sigmas spring to mind. Then there are a couple of Nikkor zooms and I seem to remember that the Tokina 17mm got good reviews back in the days.