With all the many Christian doctrines that are contained in the Bible it is important to make sure that we categorize them into a format that is easy to understand and also keeps us from dividing over things that need not divide us. Albert Mohler's article does such that in that it gives us a basic structure upon which to think critically about doctrine and then we can sort it into 1st, 2nd and 3rd level issues as necessary depending on things like how important it is to the historic Christian faith, as well as how clearly it is taught in the Scriptures.
"The King James Only Controversy by its very nature, brings disruption and contention right into the local Christian church pews." - James White
By far there are two resources available today that cover this issue that are greater than every other. I will discuss the other at another time but for today Dr. James White's The King James Controversy is in view here. This book does an excellent job of outlining the issue at hand and presenting a strong case against the exclusive use of the King James Version.
Here is another excellent debate about the exclusive use of the KJV translation of the Bible. In this debate which took place I believe in 1995 (as you can tell since James White still had hair), there are men from different backgrounds to discuss the subject. There are men representing the NKJV, NIV and NASB translation committees and there is also Samuel Gipp and others who hold to KJV Onlyism.
As always with this discussion and Dr. White does an excellent job of pointing this out, the main difference can be simplified to the idea of whether or not any one particular translation should be used exclusively or not. Whether one prefers a certain translation over another or thinks one is superior to all others is certainly a discussion to be had where there is no real division, but when one or a group claims that a certain translation should be used exclusively and the others rejected then there is a major issue.
King James Onlyism in its most extreme form is heresy of the highest order. This is the group that claims that the KJV is the Bible "re-inspired" and therefore any and all manuscripts no matter what the date or the source is fundamentally irrelevant because God's Words are perfectly inspired and preserved in the KJV.