I would say that non-Christians by definition will contradict almost everything the Bible says.
I think you missed my point... but it's not a big deal. 
Ok, let me rephrase. Non-Christians look at the Bible from a scientific perspective only.
They claim that the Scriptures is a biological inheritance from teacher to student, with human corruption in the process.
They do not take the Holy Spirit and God's direct guidance into the equation.
Okey dokey.... I would have prefered a bit more detail on your faith, but I suppose in time I can learn a bit more about how non-Catholics worship.
Fair request.
It is my unmovable faith that the Scriptures we have today are infallibe and endorsed by God, and that He has made it so that what is His Word has been pronounced canon.
But I also believe that subsequent teachings, interpretations, doctrines and dogma's are not infallible.
God has created humans, intentionally giving them free will.
This free will is an absolute necessity if God wants to be the God He is. Without free will everything we do would be by command, and none of us can be held responsible. Salvation can only be achieved by creatures of free will and similarly damnation is also a product of free will.
Therefore it is unavoidable that teachings, teachers, interpretations, doctrines and dogma's will be stained with fallible notions.
But it is also my believe that God, through His grace, will not account these fallible notions to us but forgive those who believe in Him.
Therefore, I do not think Catholics have a better chance to be saved than non-Catholics. (and vice versa)
The sins of a non-Catholic are not less than the sins of a Catholic, and the sins of a Catholic are not less accountable than the sins of a non-Catholic.