So, you are more careless and self-confident when facing an unknown threat? How does that work unless you think you are the boss and nothing could possibly threaten you? The fact alone he took two kids with him tells he doesn't really think that much of the chimera ants. It's true he's possibly like Ging in the sense he thinks one learns best through action and experience and facing deadly danger, so he didn't necessarily think there's no risk, but he did think taking the two brats with him wouldn't slow him down or endanger the mission.