I remember before XD came out, people said that they weren't going to purify Shadow Lugia because it looked so cool. So the first question is: did you?
My other question is: Where's the happiness person? I'm trying to evolve Chansey.
I purified it immediately. In my opinion, you can't really say you've won the game if you don't purify them all... And I needed to send it to my game boy anyways~