I know it's different in different countries but here in Aus, Brisbane Cat Centre have been making the Nacra 4.5 which is 15ft for a long time, this is their biggest seller with many hundreds made. they are a skeg cat that weighs about 120kg, for junior sailing weight is your friend and properly positioned beach wheels sort the weight out. I was there a couple of months ago picking up my latest 5.8 and saw a new 4.5 and 5.8 popped out of the molds, the new Nacra 15 will just add a performance factor to an already busy sector which includes the high buoyancy 3.5, 4.3, 4.5, 5.0 that Bris Cats are also making