i sail my nacra 5.2 solo95% of the time, it has 15.5m2 main and 4.12m2 jib
that's 19.62m2 total
i know the center of effort is lower than the 18sq's but then the boat is a whole lot narrower too...
wouldn't be so happy to do so on the ocean, but on an inland lake it doesn't seem too over-powered
in fact once you get used to it having crew just seems to kill the performance