How many of these church organizations still exist, I have no idea, nor do I know what they teach aside from glancing at a few websites to learn that at least some of these groups are still Saturday Sabbath keepers, Old Testament "Holyday" keepers, and keepers of such doctrines as 1st, 2nd, and 3rd tithes. Some still have an authoritarian format they adhere to, and all in the name of Jesus Christ as the "true church".
Being spiritually seduced by false teachers is a tragedy of life. Some human beings love to play the role of being God on earth and unfortunately often deceive many into following their deceptions. The Worldwide Church of God under the leadership of its original founder Herbert W. Armstrong, impacted the lives of well over a 100,000 church members worldwide. (I have read that at its peak, the membership was 145,000.) Many of those lives were spent in sorrow and tragedy, especially because of such teachings as "divorce and remarriage", and financially raping people through 1st, 2nd, and 3rd tithes, as well as pressure to endlessly donate over and above the three tithes. -Read more here