The bigger issue is that aetherytes are notorious places for pickpockets to find their marks. You're busy rematerializing from the lifestream, only to suddenly discover that your coinpurse now has a hole and is 1000 gil lighter.

Jokes aside, I wonder how the attunement process itself works. I would have guessed that you were forming a memory of the place much like you would with a soul crystal, but then again you can also attune two crystals to each other to travel to new destinations.