It is a complicated, two sided coin. If you believe in the authority of the scriptures alone, you tend to protect yourself from the Joseph Smiths and David Koresh’s of the world. On the other hand, if you believe modern men can claim the same authority, well, you open yourself up to the Joseph Smiths and David Koresh’s of the world.
I’m of the former camp, but believe that prayer is key, as well as studying the impressions and interpretations of scripture from other contemporary men (or relatively contemporary, e.g. C.S. Lewis) to possibly guide me or open my eyes to ideas that I had not thought of. I then read scripture - the only true authority - to see if what they say jibes with the word of God.
If we have truly accepted Christ, then we are protected. It is the ones who are seeking who fall prey to cults.