The White speed one exiles an attacker, the red side is a better Falter effect for another mana, nothing can block
It comes from a draw engine that converts a common game action into hand advantage, once per turn, game after game
In the screenshot, you can see that our hand has three Pokmon Goldeen, Staryu, and Seaking
Rocco, Cabaretti Caterer makes finding the perfect piece a breeze, so you can happily run a lot of silver bullet answers like Collector Ouphe, Archon of Emeria, and Soulless Jailer depending on the strategies you need to disrupt
The other consideration here is just how much value you are getting from discarding the card and whether a deck cares enough about discarding to play cards whose primary purpose is to be discarded for value