I've never had a boxer but this lady I once knew where I use to go get my hair cut had a boxer and she kept it w/her at work. The dog was real friendly and would let you pet it...she usually layed over in a corner when ever I was there--just staying out of everyone's way..

We have a lab/pit mix and she's the most loving dog ever..she gets along great with all of our other dogs--I love her to death! I think that you should go ahead and adopt that puppy..cause if you're only worried about it being aggressive I don't think you'll have a problem...dogs aren't born aggressive...things have to happen to make them that way..