Well maybe it's just semantics, but I dislike the word superior.
I don't believe we are better than non Christians. We have the amazing privilege of knowing the Lord Jesus, have received the grace and the Spirit of God and are his children. My point is, that ALL that is from God; we cannot boast that we are better, more holy, more deserving or have done anything to save ourselves. We have done nothing to earn his love or grace.
Salvation is not about good works, but I know non Christians who do more for others, give more time and money than some Christians. I have family members who are lovely, cheerful people and would do anything for anyone, while not believing in God; and members of my previous church who attended Sunday after Sunday, week in, week out but who weren't very helpful and felt they had "done their bit" when it came to serving in the church.
In the Lord's eyes, IF the latter group are truly saved and know him, they are in a better position, spiritually, than the former group - but I would still dispute it makes them superior. And to even hint to members of other religions "we are BETTER than you. WE have the true faith, you don't", would, as I said, be asking for trouble.