Is it a good idea?please help?

It's my boyfriends birthday,he gifted me a really expensive gift,so I want to do something special on his birthday.Well my idea is I want to get 20 printed t-shirts with his picture on each shirt with a caption *HAPPY BIRTHDAY* and each friend would be wearing it.. It's gonna be a surprise birthday..I'll gift him something too..But what do you people think of this idea?