Hi Lee,
A belated welcome to the Forum; this is where it is all at, as I'm sure you are discovering!
I would definitely take the paperwork with you but not tell her that you have it. I don't regard this as dishonest, although perhaps a little disingenuous. However, if you do tell her you have it and then decide you need more time to think about marriage, and do not marry her during this trip, you will put some serious doubts (and perhaps wrongful thoughts) in her mind about why you didn't marry her: "He brought the paperwork, he must have been thinking about marrying me, so why didn't he?" Thoughts of this nature would also be very hurtful to her - and I sense from your posts, particularly with regard to Plan B (which I also empaphise with!) that you have a thoughtful and caring personality.
However, I am sure you know there are always those times in life when you look back and say: "If only I had........" And by the time you make your next trip, those doubtful and wrongful thoughts may have accumulated her hurt, and she may be gone. Others may say that if she loved you and was truly committed, she would wait. But are you prepared to take that chance? Life is largely about fate and opportunities; it's those we miss that we tend to dwell on the most. It has also been my experience throughout life that you can rarely fully fathom what is in a woman's thoughts and heart, and in that respect you have to be ready to take your opportunities and shape your own fate. Taking the paperwork with you allows you to do that, and removes doubt and hurt from the equation of thought.
I hope you have a really happy time with your lady in China - and I'm sure you will make the right decision!
Johnboy