Well indeed the (modern hullshaped) F16's tops out in doublehanded mode at 160 kg max (350 lbs), F18's only go a little higher in the crew weight range (maybe 175 kg) but not by much. Of course for recreational sailing both boats carry close 200 kg and sail well.

Still the 2007 F16 global challenge champion has very comparable specs, so for 1-up sailing the F16 would actually be a rather good fit. I used to be 203 lbs myself and I have yet to complain about power.

But I agree with Chums here, if you are looking for competitive 2-up sailing at your weight of 230 lbs then the biggest boat you can get will be the best, meaning I-20. That is unless you'll be sailing with a son of nephew below 18 years of age or indeed a very small wife/girlfriend.

So the decision will be largely inspired but type of sailing you will decide to do the most. 1-up or 2-up (in a competitive sense)

Personally I underscore the desire for a spinnaker fitted boat. If you are prepared to travel up the initial learning curve then spi sailing on a cat is heaps of fun ! Even on light winded days.

Wouter