The temporary nature of the creatures isn't even a downside between ETB triggers, sacrifice synergies, and the raw damage potential, you're getting value no matter what
It depends on your format and strategy
At the beginning of your upkeep, if there are four or more creature cards exiled with this artifact, flip a coin
Imperial Recruiter can grab a Felidar Guardian, which can then blink Recruiter to get Kiki-Jiki
Black-Blue-Green are the Sultai, who revere their dead and trawl through the graveyard, all the while persisting and controlling the board Green Blue Red are the Temur, all about casting big powerful creatures, generating the mana to do so, and annihilating the opposition in a rain of dragonfire