Hard to find would have to be the HEX. Shot my first ever 300 in practice with it, and absolutely loved the roll it gave me. Something that can still be found, but are way overpriced, Super Freak. Not sure why I got rid of it. Great length for a high-load particle, with punishing power. Crushed lots of racks with that ball. My favorite Track ball ever that has been discontinued is the Phenom Unleashed. Had 2 of them, and shot my first sanctioned 300 and 800 with the second. Only reason I didn't name it above, is because Track is supposedly re-releasing this ball, same exact specs as the first one. Can't wait to get my hands on the third one!
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*Erie Community College bowling*
Buffalo bowlers are the best all around in the country.