I'm an Aussie and I had difficulties understanding parts of this but if there are any bits you'd like translated just ask. The typos don't help.
The 5.7's mentioned are the Taipan 5.7. It is the 4.9's big brother - basically identical to the 4.9 but 5.7 metres long instead of 4.9. The 5.7 is a big fast boat built for two big blokes. It is only marginally slower than the new rig Tornado and it would probably come down to who was sailing the boat.
The 5.7 has a big kite. The newer one's have cantered hulls but I have a feeling that they might end up going back to the standard arrangement as the cantered hulls are apparently quite difficult to tack.
There is a picture of someone sailing a 5.7 one up with all three sails!!! in the latest Taipan newsletter as well.
David Elliot is aka 'Slimy'. You can read more of his writing at:
http://www.taipan.asn.au see 'Slimy's Corner'.
Rob.