Would it be smart to wait to open a crystal once a certain champion gets added to it?

Sheer_Cold

My friend’s going to be getting his first 5* from the appreciation calendar, and he was saying that he’ll wait until Mysterio gets added. Is this a smart idea or no? I told him that with all the champions, it would just be smarter to NOT. What do you guys think?

Vatris

Not really because we dont know for certain how good mysterio even is and the chance of even getting him is quite low