kitesurfboard for surfing without kite?

i am thinking of getting a quad fish 5'9 from seaflight.
Seaflight designes kite surfboards. The board I was looking at is about 5,9 long, 19 wide and 2 1/2 thick.
Has anyone experience with such boards?
are they good surfable without a kite? or are they crappyer without a kite than a normal fish?
My alternative for the fish would be a 6'4'' roundtail shortboard (for bigger waves)
thanks for your answers,
Tobikey