Hi Arend,
I have seen the cats and raced against them in Australia a few times, they seem to sail OK seem fastest against other cats in light winds upwind in particular. They have boomless mainsails, the hulls are fairly heavy when compared to other Australian 16' cats. Designed to be sailed one up the hulls don't have excess bouyancy but I have seen 2 people on one but not racing.
Have often thought they would go better with a spinnaker F16 one up.

Regards Gary.