I prefer Madeleine because there is less pronunciation confusion. Madeline can be mad-uh-LIN or mad-uh-LINE (which I don't like as much).
***
Please rate my personal name lists:
www.behindthename.com/pnl/69381www.behindthename.com/pnl/69381/109399www.behindthename.com/pnl/69381/91835http://greens-end.myminicity.com/