Not cold if you dress for it. More fun than sailing on water and you don't get sea sick. Really, I have Ice boated on a DN. If you ever get the chance...take it. There is a reason people keep these for just a few rides in a winter.
I am sure they are fun, but i cant imagine it being "more fun than sailing on water"!
Can you fly a hull and soar with with raptors (Osprey), get close to pelicans sailing 8 inches above the water surface, swim with dolphins? Look down and see a flock of migrating Leopard Rays under you?