I totally disagree that F18 is related in any way to open class sailing. I haven't seen boats that are 15 years different competeting in F18 - All the 16 boats at Spring Fever were newer than 4 years and were purposely built for F18 racing. The F18 boats are built to a strict rule. You will not, however, be able to add a spinnaker and adjust the sail size on a Hobie 18 and be competitive - but we've not seen anyone attempt such a change. The Tiger and Nacra F-18 boats are terribly even in capability with neither showing a clear speed advantage in my opinion.

F18 offers sailors a spinnaker boat of a length that is manageable by most people with a power level that is manageable by most people (I'm talking male and female crews here too) that has the added bonus of putting manufacturers head to head, allowing the sailors to stick with the brand they like the most, and still be very even and competitive. I've sailed in open classes for three years and this is most certainly not one.