Gaga. She always offers something new and exciting and there's a art aspect injected into her performances. She's never predictable unlike the others. Her VMA 09 performance alone > > > >
Bey can entertain an audience with just her dancing and her OTT vocals, but GaGa can entertain the audience with her singing and OTT theatrics. Beyonce is an amazing performer but GaGa's performances are more interesting to GaGa.