I own both; and love both bags. However, if I had to choose one over the other, I would go with the BV; I have never had anything fall out of it. It is comfortable on the shoulder and it is such a chic bag. Don't get me wrong; I adore my Damier Speedy (30) but with two kids, it is easier for me to have a should bag most of the time.
Good luck on your decision!