Well, I don't live my life based on Jeremy Piven's characters (I swear that it wasn't a bad thing to wear a concert shirt to the concert before that movie), BUT I try to not wear untried/untested clothing to races. I did wear a shirt to a Half in March that was from that race, but that's because it was exactly the same as the WDW Half shirt, and I'd already run in that one. Other than that, I just never want to find that something chafes when unexpected, is uncomfy, rides up, etc, while in THE race.