i too have a thing for my f6, to give an idea what can fit in it comfortably
Nikon d300s with grip and 17-55 mounted, on one end, just below the grip has room for lens cleaning liquid and cloths and card holder.
nikon 70-300 lying back to front just below 17-55 lens.
nikon 900 flash and sigma 8-16 on the other end standing.
its super comfortable with the Domke backpack strap.
mine is olive green that was washed with liquid detergent and some bleach,
resulting in a washed out green look and the straps turned a browish green.
an f6 with real character :D