I personally love the AI Tornado for CQB environments. It is:
Easy to maintain.
Uses common airsoft materials (propane and bbs)
Is not dangerous.
Sure, it has it's place indoors, and needs to be used with good judgment outdoors.
Say what you want about the AI grenade, but I would prefer the Tornado to go off in my hand prematurely, as opposed to a homemade firecracker coated with bbs.
Ár skal rísa, sá er annars vill
fé eða fjör hafa. Sjaldan liggjandi úlfur
lær um getur né sofandi maður sigur.