BTW I didn't translate Luffy's last sentence(the one he says after he says he went to hell) because i was in the hospital and I didn't know how to translate it correctly in english. And now i can't give an exact translation but Luffy means that he is superior/has the advantage/etc. to them because he has already gone to hell. Basically the translation would be
"I went to hell many times already, i'm superior!!"
But I'll wait for the official translation to see how they translate that