It's just free to play.
What I understood, HorizonXI is trying something different than what Eden and Wings failed to do.
Well they all have one thing in common: They're all violating Square-Enix's rights, and they're all costing SE money, and they're all harming the live game. Maybe that's what they want. Doesn't make it right.

And to be clear, I like the game as it is now. I don't want to be capped to 75, I don't want broken content/mechanics/whatever else, I don't mind paying a sub and I don't want what those servers offer. And they all jeapordize the rest of ours' ability to play the official game.