Thanks for the comprehensive response, Wouter.

It seems that if I want to sail the Taipan as an F16, it will be far more competitive as a 1-up - which is what I thought.

There is still plenty of good racing to be had for Taipans without spinnakers and I think my boys aren't quite strong enough for a spinnaker yet anyway.

Looks like it is a Taipan sloop/Taipan F16 unirig combination for me.

Hopefully my boys get stronger and keener and make me buy them a Viper in 2 years time anyway - and that would be a fantastic outcome!