Same GC Ifrit killers gets better reward

[Ava]

Please Devs get us some clarification on this before patch day

You have said before that we shouldn't worry which GC we choose, however:

I cannot choose my GC "freely" knowing that I may be missing out on better loot or possibly exclusive loot from Ifrit by doing so.

Could you please explain what exactly is the "greater reward" from defeating Ifrit by members all of the same GC?

Thanks

I'm fine with this under one condition: The "bonus" item is a vanity drop.

But with SE's track history with FFXIV I have my doubts. I really wanted to pick the Gridania Grand Company but now I feel like I'm probably going to be forced to pick Uldah.