75 kg, 15 year sailor. I sail in lakes, rivers, bays & ocean, some places with strong tides that affect water state & board/sail choice.
F5 has too many possibilities from formula & 10 meter on a flood down to 85 liter wave & 5.5 on a strong ebb tide.
F6 would usually have me on an 85 liter wave & 5.0, 4.5 or 4.0 on an ebb. May even bust out the 72 liter wave & 5.0. Flood would have me on a 93 liter Freeride with 5.5, 5.0 or 4.5 sails.
F7 would be only wave gear. 85 or 72 liter & 4.5 or 4.0 sail