Hi Alan, I can recommend the Mystere 5.5. It is nearly as fast as the 6.0 and probably the fastest 18 footer on the market w/o a spinnaker. It has nearly identical hulls to the 6.0 which allows it to carry a big load and/or crew for cruising or allows it to be pushed hard for racing. It would not be difficult to add a spinnaker and snuffer set-up and have a very fast 18' spinnaker cat and possibly for Formula 18 racing. You will find that the Mystere owner you met will stand behind his boats for any service work you may ever need, also. Go for it!!
Mike Fahle