Heartmender Circle grants 25 MP5 and Band of the Invoker grants 50 Spirit. Otherwise these Emblem of Triumph rings are identical. Depending on the amount of mana regen an ele shaman has and the fight length, these two items should be worth the same amount or with the sizable regen afforded to ele shamans, the Heartmender Circle rated slightly higher. As of 2.2.19, the Band of the Invoker is significantly higher than the Heartmender Circle, yet shamans receive trivial gains from spirit overall and none inside the five second window.