I decided to not take the chance. I bought the books, but I'm not touching them until the series is complete.
I just finished book 2, and I am really enjoying it. In most book/movie combos the book goes much deeper in detail than the movie has time for. But unlike most The Expanse series actually has MORE detail and subplots than the books. The series adds additional subplots that are not in the books, as opposed to the usual opposite.
One thing that remains true to both: Avasarala has the best lines.