Is Libra/Forma worth upgrading if you already have a Clara and H20 Edition 2?

I have Kindle Oasis,Clara HD and the Aura H2O Edition 2 6.8" still very good devices. Is the Libra or Forma worth the upgrade or am I better off sticking with my 6.8" H2O?
Just curious how people feel about it that also have the Oasis/Clara/ H2O 6.8"/Forma

Thanks