I haven't, but know lots of people who have.
Level of neurosis could both hurt and harm your chances of flyballing successfully, LOL. Some dogs that are too ball driven do get a little OCD over it and will injure themselves smashing the box to release the ball. If your dogs isn't quite focused enough they can be disturbed by the other dogs and people around.
I say, find a class, try it out and have fun! If nothing else it could be a great bonding experience.
"I'm so scared of eventually succumbing to saggy butt that I'm going to sacrifice my dog this evening. Anyone for some German Shepherd Pie?" - daisychain
"Well! Fruit is stupid! These onions taste nothing like fruit!" -allularpunk