Concurrent Infusions is a 4th level Artificer infusion that lets you apply the effects of three 1st level infusions, all at once, without actually 'casting' them.
You channel your artificer talents through an increased number of minor infusions. When you cast this infusion, you can imbue the target object with the effects of three different 1st-level infusions chosen at the time of casting. The infusions function exactly as if you had cast them on the object, and do not count against your daily allotment. (emphasis mine)
The argument I've seen is that this is insanely broken, as it lets you use 1st level infusions without paying the XP cost or material components (in particular, Spell Storing Item lets you cast any 4th level or lower spell in the game). However, the section I've bolded makes me wonder if that's actually the case. Does it refer only to the effects of the infusions, or does it mean you also have to pay their costs "exactly as if you had cast them"? Is there any precedent one way or the other?