For the past year & a half, I've been using the used balls that came w/ my used table. They play fine & have some scratches, but no nicks or chips. I believe they are phenolic. Just for kicks, last night we played w/ a set of Cyclop Ladons I bought off eBay a few months ago. My wife & I both played noticeably better and I had far more action on the cue ball than w/ my usual set of balls. I know the quality of a set of balls can affect the durability, but can a ball affect playability too (if both sets are in good condition)?