Hi Elfish,
where are you sailing? If possibile do test sailing before buying. Maybe somebody can offer you a trip.
What is your current boat?
Most of the time I am sailing with my wife, we are about 125...130 kg or so, and that's just fine. We have less than the maximum sail area (no jib), but good winds.
From time to time I sailed with male friends and it was ok, but felt heavy (not realy slow, but calm). Wouldn't sail it with three, but I wouldn't do with most cats.
Age. It is less a question of age, than of strength and weight. If you and your crew can handle a H16, you can handle a F16 as well.
Cheers,
Klaus