100-110 Level Up 25 mins solo per level or 50 min with a 110 helping (world quest)

There is this spot that spawns demons from a portal every 4-5 seconds

Coords 32,32 on the Broken Shore, on the little island right near Dalaran.

The NPCs grant 200 xp each no matter the level if within a group or ~600 xp if solo without any xp buffs. Basically it takes 50 min to levelup a char there or 25 min if the character can kill solo