I don't like either...
I don't like Alexander, but for some reason love Alexandra (or, even better, Aleksandra) for a girl. I don't like Alex though, and that's the inevitable nickname.
I hate Victoria because it reminds me of the queen, who looked and sounded as though she was a right miserable sod. Also, because it gets shortened to Vicky (ugh) or Tori (ugh).
But I'm sure I'm in the minority about these names!