ok, I understand.
I don't know how steady you have the wind over there in West Kirby in 12k conditions, but where I surf 12k conditions also often mean a lot of lulls in which the US147 happens to excell. It probably depends on the wind direction.
The introduction of the US147 would also imply a higher usage of the IS110 of course.
IS87 / IS101 / IS122 / US147