Hi Cathy,
Miles is a wonderful name and if it is what you really want for your baby - you should do it. The important thing is to choose a name that you and your husband mutually agree on. If this is the one, then this is the one.
My husband and I thought really hard about a name for our son and we considered the "teasing" factor also. We tried really hard to come up with a name that couldn't be shortened etc. Guess what - the kids still found a way to tease, make up a rhyme or mess with his initials! Kids are creative - I'll give them that. One 6 year old kid even saw him wearing a "NEMO" shirt, looked over his shoulder and said "Ha! Your name is NEMO spelled backwards and upside down!" Clever kid. (You can probably figure out my son's name now).
My point is - even if you came up with a name that you liked less - they would still find some way to play with it and then you would really be upset.
I also agree with one of the other posts that most kids won't know who Miles Davis is until they are mature enough to be past the teasing stage - any yes he was a great musician. There are worse things to be teased about.
Sometimes you have to see your baby first before the name really fits. When he is born, you may look at him and think Miles is perfect for him...or something else may suddenly inspire you.
Piece of advice - if you REALLY like a name - don't share it with family/friends till he's born. I did this, and many of their comments, (though well meant), stopped me from considering those names. Once he's born and named - every one will congratulate you on his name.
Sending you lots of good vibes for the remainder of your pregnancy and delivery....
S.