Aside from the performance comparisons I think the Pitts has a certain something that is immediately evident as soon as you leave the ground; it's definitely a rewarding aircraft to fly. It's also reasonably affordable, particularly if it's kept on a permit, and you can homebuild some models too. The design is quite old now but they do seem to last once their built with a reasonable amount of care. I think that is why there are still so many kicking about today and hence their popularity as a cost effective competition ship.