>>4302742F5 is best value for money. F100 is lighter, but cost almost as much as the F5 which has many more features and is built like a brick shit house. F6 is built like the F5 but they're still like 1000 bucks for one.
F5 is the nice happy median between price and build quality. The AF is amazing on the F5 and the AA battery pack with a set of new Eneloop batteries will outlive you. I charged my set up when I bought it two years ago and have put probably 20 rolls through it and still showing max power.
Took it on a hike through Moab pic related and it was like 100 degrees outside it does not give two shits. I dropped it loading a roll of film like an idiot it just keeps going. The F5 is the Ford 300 I-6 of the 35mm world, when aliens discover our remains of our civilization 50000 years from now they're going to find one of these things and finish the roll of film in it.
F5 and F3 w/motor drive are the GOAT for Nikon 35mm. Honorable mention to the original F as well, also GOATed.