Mark,

I'm a 2004 Nacra F18 owner and have sailed Hobie Tigers and have only seen the Infusion. I can tell you that from a competitive standpoint, the Tiger probably has a little more development ready to purchase in the sails -but that the hull design hasn't seen a major change in quite some time (I understand that the daggerboard placement changed recently). Part of the reason you see such a large price desparigy is that the Tiger is imported from France while the Nacra is made in California. Another part might be (and I'm really guessing here) is that Nacra might be trying to undo some damage caused by broken promises when Infusions weren't available when they were supposed to be. I really expect the Infusion price to go up before long.

The Tiger platform has a lot of history with it and it has continued to prove that it is up to the challenge in F18 sailing and has continued to be a very competitive platform. Personally, there are a couple of minor quirky things that I don't like with the Tiger - the trampoline attachment method (too spongy) and the feel of the helm. However, I wouldn't hesitate to race one again given the opportunity.

The Infusion does have some of the newer buzz items - the low mounted jib, gybing daggerboards, and comes with better more complete rigging. I much prefer the side laced trampoline and the feel of the helm on the Nacra. The Infusion is a new boat so there are probably some teething problems from manufacturing - but Nacra does stand up and make those right pretty quickly.

I really think you should try to get a test sail on some and see for yourself...but I don't think you will find any significant competitive differences between any of the four platforms in the US (Capricorn, Tiger, Infusion, '04-'05 Nacra F18)