I would seriously consider a US147 in preference to my Is137, however, I would want to be sure that I was alowed to race it
I looked at the Is127 and Is137, ultimately going for the 137 because those few cm extra length make it much more pleasant in marginal conditions.
I had 28.3kts on it with my 9.6 the other day, when I changed down to the 7.8 on my Is110 all I could manage was 27.1kts, only changed down as broke the mast on 9.6, I am not really sure what the 137 gives away to the 127. It would have been nice to see what a US147 could do in those conditions, which are cross over from the 137 to 110
When you think about it, it is really incredible what these "big" boards can do - sustaining 28kts in 15kts wind with massive sails. Maxed out on my IS87 with 5.7 on flatish water in Portland Harbour, I am only doing 37kts peak, but over 500m only 33 or 34 kts