Is Kingpin worth 6* Sig Stones?

JragonMaster170

I was revisiting my duped 6* Kingpin over the weekend, and I'm blown away. His damage and purify abilities are great. I've got sig stones to pump up his signature ability. Is he worth the sigs?

Ercarret

There's no need to max out his sig, but I personally put some sigs into him. At sig 65, he gains three Rage stacks at the start of the fight. That's kind of the sweet spot for me.