I'm reviving this thread because I just got a beautiful pearly orange factory second Underworld today. I threw it a few times too, and it flew like a beat River. I really enjoyed it's slow turnover and the ease with which it can be hyzer flipped. It was pretty cold today, so I'm sure it will fly differently in different conditions, but I'm bagging this one.
Star Firebird - 2 QOLFs (1.1 and 1.2) - Star and Champ Teebird - Star Sidewinder - 2 GL Rivers - Champ Katana
Z Hornet - ESP Zone - ESP Buzzz - Z and ESP Comets
N Anode -N and P Ion