New Kid Tuesday

Maybe this is because of my lack of teaching experience, or because I just don't understand people, especially parents, but...
I don't know why parents move their kids with 8 weeks left in the school year. I mean, I'm not sure why parents move their kid to a new school the DAY BEFORE TAKS. That's actually the least of my worries...
The registrar knocks on my door to bring in a new kid. (She had warned me the day before that he would be coming.) He comes in, seems like a happy kid (which is a characteristic I like). A lot of my kiddos go up and shake his hand and introduce themselves. I told him that he wouldn't remember their names until he had heard them many times later, but my class was trying to be polite. (This is a HUGE HUGE HUGE step in the right direction!!!!!)
I got him situated and the rest of the class to work so I could figure out what we were going to do. We had a class meeting where the class wouldn't stop talking and asking David questions.
He seems like a good kid. He looks like a soccer player, so I ask him about that and tell him we are the kickball class. The class continues to talk about kickball and that I'm the best kickball player. (**SMILE**)
He automatically likes that I play kickball and one of their rewards is kickball, which is a great thing.
During specials, I find out that he wanted to request his class because he had a friend at this school. This friend is not such a good choice. He's been in trouble many times before...not good news.
As the day goes by, I have positive thoughts about this kid, but then.............
During car rider duty another teacher comes up to me, "So, I hear you have one of my previous students."
Me: "I do? Who?"
Teacher: "David. I just want to let you know what's up..."
She goes on to tell me how he was at the top of her list of concerns in many details. This got me thinking...At the end of the day, I can't decide if I wanted to know that he has had a bad past or if I wanted to think he was a good kid and then deal with it when he makes bad decisions.
Which is better...having previous information that will give you a preconceived idea or not knowing anything and dealing with things as they come?

DID I MENTION THAT I'M EXPECTING ANOTHER NEW KID (BOY) BY WEEK'S END??????