watch out. for contests you sometimes have to have the original on stage with you on your stand and copies of this given to the judges. i know thats how it works for chamber music comps anyway. have you got a piano accompanist? and what grade are you about. (i haven't sat any, but my teacher thinks grade 6 (english grades like trinity))
Mozarts pieces are fun. but sometimes can be more difficult then they appear. ask your teacher. they usually ahve A LOT of music and may be able to accompany you. if you dont have a teacher - GET A TEACHER they are very helpful in preparing you for comps.