re: Big Green egg VS ?

Even at 700 degrees, the exterior ceramic surface of the BGE won't give you a contact burn. Of more concern than the exterior temp of the cooker is the flashback potential. If the balcony is covered or very enclosed, you want to make sure the adjacent surfaces are fairly heatproof (ie, stucco, brick, cement fiberboard siding). I would strongly discourage placing any ceramic cooker beneath a vinyl clad overhang or near vinyl siding. I've burned off arm hair, singed more than one potholder, and fried the leaves off of a nearby plant (and I'm fairly careful). A careless sort could easily shoot fire up to the neighbor's balcony, causing all sorts of trouble.

Flashback video & info: LINK
Scroll ahead to 1:05-08 to see the slow-mo flashback fire.