Back in 1999 I designed a IOM and made some basic hull plans avalible on the web.
3 or 4 have been built as far as I am aware.
Maarten Adriaans in the Netherlands has built a nice example which you can see here.
As you can see he has made a fine job,both designer and builder are happy.
The boat looks nice on the water,I never did build to this design myself so I am unsure of the performance.