Puzzle 57 - Polyominous 12

I made this puzzle a little bit differently than usual for Polyominous.  I usually make the pattern of givens before the rest of the puzzle, but this time I just made things as I felt like then mirrored the rest to make it symmetrical, and out came this.  I might do this more often.

Edit: Well, looks like we're playing Spot the Asymmetry again.  Oh well.