I agree with what other people have pointed out about the Chiefs, that both they and we will be different teams come January.
However, I don't think people should sleep on them. They beat us once and they'll have the confidence they can do so again. They'll still match up well with us when they have the ball and their pass rush always has a chance to get home, which is a historical recipe for beating us.
I still think we beat them, but I think they give us the most problems of any AFC team, moreso than the Steelers do. It actually might be a good thing that we played and lost to them early on, because that'll help Belichick convince the team to take them seriously if we play them again, and also gives us some film on individual matchups.