Don't let this level fool you. This level is not symmetrical. It really isn't.
5 months ago, I tried this level maybe 50, maybe 100 times in the first week I signed up (I can't tell the exact number of attempts because of undo button). ...and all of these attempts were done on the right side of the puzzle.
But 5 months later, this morning, when I saw a review about it, I wanted to try again and managed to solve it, quickly. ...from the left side this time, not the right side.
And with this solution, I realized that the unsymmetrical thing is not the level, but myself.
10 stars out of 5.