TBH you shouldn't even be running Air Balloon. Leftovers is a must on Sableye. I mean, what happens if you run into a MKanga that uses Crunch over Earthquake? And now you have a wasted item slot.Sorry, my bad. I'm not too familiar with using Sableye. All I knew was that Ghost typing plus fast or Prankster Wil-o-wisp was a good answer to Khan. The Air Balloon lets Sableye come in on predicted Earthquakes, and should Khan be running Crunch max Defense plus Recover should leave Sableye in a good position.
But anyway, this shouldn't be discussed here. You want to discuss Sableye builds, go to the Sableye thread.