John MacArthur
A Nine Commandment Protestant
  "There is no question about ... nine commandments being permanent and binding."

Here is the sermon Understanding the Sabbath by John MacArthur of Grace to You, Unleashing God's Truth One Verse At A Time. He makes the following assertion:
"I think it's legitimate to consider Seventh Day Adventism as a cult because they believe that the writings of Ellen G. White are inspired by God and could be put alongside the Bible. But they identify themselves as faithful to the fourth command."
He then attempts to demonstrate that the Sabbath commandment was abrogated by Jesus. The Bible clearly states that the gift of prophecy, and commandment keeping, are clearly characteristic of the true church just prior to the second coming:
Joel 2:28-31 (KJV):

28 And it shall come to pass afterward, that I will pour out my spirit upon all flesh; and your sons and your daughters shall prophesy, your old men shall dream dreams, your young men shall see visions:
29 And also upon the servants and upon the handmaids in those days will I pour out my spirit.
30 And I will shew wonders in the heavens and in the earth, blood, and fire, and pillars of smoke.
31 The sun shall be turned into darkness, and the moon into blood, before the great and terrible day of the LORD come.

Rev 12:17 (KJV):
17 And the dragon was wroth with the woman, and went to make war with the remnant of her seed, which keep the commandments of God, and have the testimony of Jesus Christ.
Rev 19:10 (KJV):
10 ... worship God: for the testimony of Jesus is the spirit of prophecy.
Rev 4:11 (KJV):
 11 Thou art worthy, O Lord, to receive glory and honour and power: for thou hast created all things, and for thy pleasure they are and were created.
Rev 14:6-12 (KJV):

 6 And I saw another angel fly in the midst of heaven, having the everlasting gospel to preach unto them that dwell on the earth, and to every nation, and kindred, and tongue, and people,
 7 Saying with a loud voice, Fear God, and give glory to him; for the hour of his judgment is come: and worship him that made heaven, and earth, and the sea, and the fountains of waters.
 8 And there followed another angel, saying, Babylon is fallen, is fallen, that great city, because she made all nations drink of the wine of the wrath of her fornication.
 9 And the third angel followed them, saying with a loud voice, If any man worship the beast and his image, and receive his mark in his forehead, or in his hand,
 10 The same shall drink of the wine of the wrath of God, which is poured out without mixture into the cup of his indignation; and he shall be tormented with fire and brimstone in the presence of the holy angels, and in the presence of the Lamb:
 11 And the smoke of their torment ascendeth up for ever and ever: and they have no rest day nor night, who worship the beast and his image, and whosoever receiveth the mark of his name.
 12 Here is the patience of the saints: here are they that keep the commandments of God, and the faith of Jesus.

Note that Revelation 14:7 is a quote of the 4th Commandment:

Exodus 20:8-11 (KJV):
8 Remember the sabbath day, to keep it holy.
9 Six days shalt thou labour, and do all thy work:
10 But the seventh day is the sabbath of the LORD thy God: in it thou shalt not do any work, thou, nor thy son, nor thy daughter, thy manservant, nor thy maidservant, nor thy cattle, nor thy stranger that is within thy gates:|
11 For in six days the LORD made heaven and earth, the sea, and all that in them is, and rested the seventh day: wherefore the LORD blessed the sabbath day, and hallowed it. 
So in labeling them a cult, John MacArthur makes a point of highlighting defining characteristics of the true church just prior to the second coming, according to the Bible, and singles out only the Seventh-day Adventists as having them, the very points that anger Satan (Rev. 12:17), they worship the Creator by faithfully keeping His seventh day Sabbath, and they have the testimony of Jesus, the spirit of prophecy. They are preaching the everlasting gospel (Rev. 14:6-12), but the 9 Commandment Protestants are not, because when you will not hear the law of God, neither will you tolerate the straight testimony of a prophet of God calling for repentance and obedience:

Isaiah 30:8-10 (KJV):

8 Now go, write it before them in a table, and note it in a book, that it may be for the time to come for ever and ever:
9 That this is a rebellious people, lying children, children that will not hear the law of the Lord:
10 Which say to the seers, See not; and to the prophets, Prophesy not unto us right things, speak unto us smooth things, prophesy deceits:
Proverbs 29:18 (KJV):
18 Where there is no [prophetic] vision, the people perish: but he that keepeth the law, happy is he.
As for his arguments regarding the abrogation of the Sabbath commandment, see the articles below.

Identifying the True Church Proclaiming The Elijah Message From Scripture
Sunday is NOT the biblical Sabbath day.
Rome's Challenge to Protestants
Did the Apostles keep Sunday?
The Mark of the Beast and the Seal of God
The Mark Of The Beast In Daniel 8 - 12
The Seal of God in the Old and New Covenants
The Battle of Armageddon.