I don't know where you have been, but ICF's are not an "easy" sell...IMO.
They have been around in my area more then 30 years, and we still have trouble selling the upside...even here, in tornado country. The energy numbers cannot be beat...but then again, most people I know get excited when they see them, and as they get serious in a new home plan, they stick with traditional construction, rather then the "new" and better way.