Sounds like he's still bringing the porn into his life?
That is a problem.
I agree that it would be a good idea for him to keep away from the porn completely. My own view of it is - many people are exposed to it; it gets sent into our emails without our permission even when we put filters on, but it is an unhealthy way to view others because he might bring the unhealthy ideas into your relationship; it's offensive; but many people have the curiosity; and since it is so readily available on the internet - very easy to find; but I've known of people who lost their job because of it. It is a serious problem.

I wouldn't start producing children if you're unsure about even staying together.

Thanks goodness that you are doing well in your schooling.
It is touching that he says that you are the best thing that ever happened to him. I wonder if he means it? Maybe he takes you for granted? Hope that's not the case. Does he realize that you might leave the relationship because of his cyber cheating/porn problem?
Maybe he should realize this.

You know him fairly well, or so you think - what is your sense of his genuineness and commitment?
All the best to you.