Baby-Doll Eyes is a Fairy-type move introduced in Gen. VI that reads as follows:
The user stares at the target with its baby-doll eyes, which lowers its Attack stat. This move always goes first.
The move Charm has been changed from Normal to Fairy in Gen. VI.
The user gazes at the target rather charmingly, making it less wary. This harshly lowers its Attack stat.
Baby-Doll Eyes is 30 PP and Charm is 20 PP.
While Charm's "harsh" status is often preferred, I'm unsure whether or not that makes it more or less advantageous than Baby-Doll Eyes's ability to always go first. How do these two moves compare to each other and in what situations would one be more advantageous than the other?
In my specific case, I have Charm already on my Eevee, which I would eventually like to evolve into a Sylveon. I only need one Fairy-type move to meet that requirement and having both of them would feel redundant. While I don't plan on doing any competitive play, both regular gameplay tips and any relevant information for competitive play (if there is any to be had) would be appreciated.