I have only played in one PAPA circuit event at EXPO and had a blast. I think you need to play every machine more than once unless you are one of those super elite players. I play for fun, but if you want to look and see what those players did, just check this out:
http://slam-tilt.com/expo/playerIndex.php?disp=player
For example if you look at Bowen:
http://slam-tilt.com/expo/playerIndex.php?disp=player&pid=5 - at the bottom you can see he played a few games only once but others several times.