There are probably few of us who haven’t been visited at least once by Mormon missionaries. At some point these young men will ask me to accept a copy of the Book of Mormon, read it, and pray about it, asking the Lord to "send the Holy Ghost to witness that it is true." Then, they’ll "testify" to me that they know the Book of Mormon is factual, that it’s God’s inspired word, and that it contains the "fullness of the everlasting gospel."
They always assure me that if I read their text with a prayerful spirit, I will receive the testimony of the Holy Ghost. That testimony supposedly will convine me beyond doubt that the Book of Mormon is exactly what they say it is.
The missionaries want me to have a feeling about the Book of Mormon after reading it. They describe it as a warm, fuzzy feeling—after reading and praying about it. This feeling is the proof that the Book of Mormon is inspired Scripture. From there they conclude everything else about their religion should be considered truth.
I try to explain to them that feelings are sometimes misguided and ask them why they feel the text is inspired. The answer is always 'because Joseph Smith said it was and the Book of Morman itself says that Joseph Smith is a prophet'. After that is said, it is not difficult to point out the failed prophesies of Joseph Smith that are found in 'Doctrines and Covenants'. One that says there are people on the moon that dress a lot like Quakers and another the lost civilization living in Antarctica that has their own scriptures. I point out that If there were even one false prophecy it means Joseph Smith was a false prophet.
In my area, there are quite a few Morman churches and an abundance of Morman missionaries. They have a 'seminary' where the youngsters are trained. I've found that none of them have any background in Church history and when confronted with the fact that none of the peculiar LDS doctrines are found in the early Church. When asked why if LDS is a restoration of the true Church these doctrines are not found in any of the writings of the ECF's there are just blank stares.