I had an F100 for a while and thought it couldn't be better... until I picked up an F5.
When I hear "best" with no qualifications, I think of the relevant camera that does it's job (to take pictures) most effectively - a workhorse, basically. To that end, the F6 and EOS 1V came too late in the game, so it would have to be the Nikon F5 - long production life, very effective journalistic camera.
Of course if you are a camera manufacturer, your definition is probably centered around number of sales or profit, in which case maybe it would be something like the Canon AE-1? 🙄