These rings are bad for sublimation effect. They will decrease the limit of MP you can obtain using sublimation. Whereas rings like Serket, or Astral will not.
Like Jubano said if you are using sublimation you shouldn't use this ring. Serket and Astral are a bit expensive but Ether Ring is cheap. Use in the other slot something like Tamas, Bomb Queen (if you're taru specially) or even Mana Ring if you don't have money. Try to avoid -HP gear if possible.