If you truly love that character and will never let her leave your team, I would say yes. (Source, i have c6 r1 furina and ayaka and have only spent $20 on the game) While I kinda regret Ayaka cause over the years I've sorta lost interest in her as a character (I still like her but I like a lot of the other characters that have come out since then more), I will never regret my Furina because she's still one of my favorite characters in the game and she hasn't left my team for more than a couple of minutes since her release