The 4.9 has been around for a while now, and is still the bench mark small cat in Aus.
They have the advantage of being well developed.
A well sailed Taipan is a fast boat and will be hard to beat in most conditions.
My advise, for what it's worth, is, get your self a Taipan, stay Taipan legal, and enjoy.
Put on a spinnaker and enjoy the best of both worlds.
Regards Tony