Vanderhoven7, you made a number of good points in a post on page 5 of this topic thread. However, I disagree with your statement that William Miller was "... the founder of the Seventh Day Adventists ...". He did not found the Seventh-day Adventist religion, though he did start the "... mid-19th-century North American religious movement known as Millerism. (see https://en.wikipedia.org/wiki/William_Miller_(preacher) ). That movement was one which believed that the second advent of Christ was imminent (and thus it was a second adventist movement). But Miller was a baptist preacher (and for a period of time before starting the movement he was a deist) and to my knowledge he never joined the Seventh Day Adventist church. I think he also observed the Christian Sabbath on Sundays instead of Saturdays.
What became the Seventh-day Adventist church was influenced by Miller's ideas and it adopted some of his ideas, but that church was not founded by Miller. Likewise Russell's Bible Students movement adopted some of Miller's ideas, but the Bible Students (and the Jehovah's Witnesses) was not founded by Miller. The above mentioned Wikipedia page has a chart called "Reaction of Millerites to the Great Disappointment". It mentions the reactions that various Millerites had to Miller's message and some of the religions which formed as a result of such reactions. Since Seventh-day Adventist church is one of those religions, what you said is nearly correct.