AsapSCIENCE has the answer!

Usually when you use a public restroom, you don't have the choice. It's either the hand dryer or the paper towels. But given the choice, the paper towels are the better option for clean hands.

This, of course, if you're washing your hands properly.

As for the environment, the newer hand dryers are the best option, since we toss something like 13 billion pounds of paper towels into the trash a year.

Check out the video, the guys from AsapSCIENCE explain everything!