I've had some interesting experiences talking with Mormons. Recently I lent 2 missionaries a book of the facsimiles taken from the Pearl of Great Price, which has 'new scripture' in it. The Book of Abraham shows immediately that ol' Joseph Smith was a very cunning and deceitful guy.
Joseph Smith bought some papyrii excavated from Egypt from someone passing thru his area. He declared that they were actual autobiographical writings from Abraham! No one knew Egyptian back then, as the Rosetta stone was not yet discovered. So no one was able to disprove his claim.
Then, when the Rosetta stone was discovered a number of years ago, the original papyrii were not available to check the translation. However, the Smithsonian discovered the originals in their storage area (in the 1970s I think), and returned it to the church--and Egyptologists have unanimously rejected Smith's translation. The Book of Abraham is a copy of a funeral rites text, commonly buried with mummies. More than one Mormon has left the church on account of this exposure--and these days, the Mormons barely pay attention to this book, in order to avoid troubles in their ranks.
Both Joseph Smith and CT Russel were masons-- the Mormon temple rite is actually almost verbatim the same as masonic temple rite.
Smith enjoyed giving talks on everything. He was quoted as saying that the moon was inhabited by folks who dressed like Quakers, and were about 6 feet tall.
Smith was a womanizer, too. Before the everlasting covenant of plural marriage came out (and lasted only 50 years!), Smith had been secretly seducing several women, married and single, telling them that God had given him the word that they were his wife for eternity, so relations were ok. Compare Russell.
Smith's wife, like Russell's wife, got aggravated at her husband's enormous ego. There were spats.
There was a big power struggle after the death of Joseph Smith.
Mormons and JWs avoid the message in the Bible by different methods. JWs just mistranslate the Bible to say what they want it to say; Mormons say the Bible was corrupted, and Smith is God's prophet, restoring the 'lost' gospel.
Mormons are told to avoid independent thinking. They are warned against reading materials by their apostates (or any one else; this is 'persecution').
There are lots of similarities in changes of doctrines (e.g., "Adam is God", espoused by Brigham Young; quietly reversed later on...).
With all these troubles, their ace in the hole is "the burning bosom". This clutching at a warm feeling of certainty is what their testimony stands on, even when all else fails.
But my sister-in-law, her husband, and their 4 kids all came out of the Mormon church after 24 years in it. So, even her burning bosom couldn't withstand the proof that hit her hard on the web.
This internet is a pretty good thing, just for her sake alone.