Very easy to apply and looks professionally drawn! Went on easily without any wrinkles, just make sure you "level" the lettering, because once they've been stuck on, there's no taking it off. Our walls are the "old school" plaster, so there's a lot of nooks and crannies that I thought would interfere with the how it stuck, but it worked out perfectly.
Just watch the video on YouTube which gives you visual directions and tips for a painless application. One suggestion I'd like to make is, would like "parallel" lettering to fit between the pictures which would give it a more uniform effect. 
Pretty neat and doesn't cost a fortune! You don't have to have strangers in your home to give you that "custom" effect. I will purchase different appliqués for more walls!