if thatÃ‚Â´s an npw5, i learnt kitesurfing in one of those.
I really love this kites, but its performance sucks
the wind window is about 90 or 100 deg, and it moves really slowly trough the wind window
and it takes a few sesion to get used to it
I think something similar to a 14 inflatable would be a 10 or 12 sqm npw5
there are plans and programs for this kite all over the net
anyway, thereÃ‚Â´s an improved version that has a wider wind window a pulls harder. itÃ‚Â´s called npw9.
heres a link that has a calculator to build this kite