(Pet/Guardian/Companion/Minion/Mirror Image)'s follow distance

Hello, I'm on the "quest" of looking for any sort of information regarding what should be the default (Pets/Guardians/Companions/Minions/Mirror Images)'s following distance in or out of combat (you know that distance between and that separates Player and the "Semi-NPC?" Partner).

Any information from Dks, Hunts, Locks, Mages, that can lead to official statements about this made by Bli$$ard or Retail players by the moment would be really appreciated. PM or posted it here, thank you.