Wether or not you use fanning powder is up to you. I won't write a whole essay cuz i've already done it many times but i'll say this:
Fanning powder will:
Makes your fans better
Make your spreads better
Make packets stick together more in cut and ariels.
They take a while to get use to them but to me, they are pure gold. I have no idea how i managed to flourish before i got these. But it may make it harder to do color changes RIGHT WHEN IT PUT ON. Let the powder settle for a couple days, meaning do some flourishes with that deck, and you should be able to do color changes just fine.