the 15.5 is kind of slow, normally.
but you shoud try to fly it with shorter lines. I tried it with 20 m lines an I had a blast! It turns so quick, you wonÃ‚Â´t believe the difference. Unfortunately you need a little more wind, since with longer lines you get more power. Therefore you can fly it in stronger winds. But then you have a really great time and get big airs! IsnÃ‚Â´t that why we love this sport?!