Mozart's symphonic works alone are more complex than what Gaga does. Take the 40th, the harmonies, the transitions, the sheer beauty of it. Despite the huge technical challenges of composing for a Symphony, still add that much beauty to it. And then there are vocal works, Opera, chamber groups... He was a huge influence on Beethoven, and a couple other cats... Mozart beats Gaga in complexity and inspiration. I feel funny having actually typed this comment...