Live performances are everything, it was hard to call any of these "the worst" and not choose all of them for the best.
Best:
Aphrodite - Subomie - I just, had to. Phenomenal performance; it's a shame you couldn't submit the entire Les Folies Tour so I'd have an excuse to watch it again.
Promise This - BlazingLovatic - The adlibs and breakdown added a nice, new spin to a song/performance that was already practically flawless. Great execution, really captured my attention and kept it from start to finish, despite me having seen it multiple times before.
My Songs Know What You Did In The Dark - Miles Caulfield - First time seeing this, went in expecting very little and came out with chills. The vocals, the atmosphere, the inclusion of Taylor- it all came together marvelously. You picked the perfect performance for this type of game and got FOB giving even the biggest pop girls a run for their money.
Worst:
Blow - keshaspearsxo - I'm sorry, but she sounded so dead and out of it. This is not the type of energy I would expect from a Ke$ha performance.
The One That Got Away - Ferst - "sing her best to the audience
without any gimmicks", so without anything that makes her any bit of an enticing performer?

bad call. and unlike Sebas' choice, this wasn't even a good vocal showcase.
212 - Jax Great Vocals- Don't hear it. Sick Flow- Questionable. Hype Crowd- Only because it's a popular song.
Honorable mentions: iHype - Without You, Ain't No Other Man - EuphorianSea/Truth Teller, Lost - Sebas, Is It A Crime - Cristhian, Bang Bang - Citrus