Well seeing as neither of them are albums, that makes it a little tricky to pick :3
But to decide which is the better EP, I think that Scary Monster and Nice Sprites is probably better because the only songs which aren't 100% his are Scatta (ft. Foreign Beggars) & All I ask of you(ft. Penny) However, on Bangarang the only songs that are 100% his are Right In & Bangarang. Don't get me wrong both albums are insane but I just like Scary Monsters better :3