Interesting question, thank you Hbert997; I had never even heard of "Greek primacy" before.
I did an internet search and this is a short definition I found on
enotes dot com:
"Greek Primacy is the view that the New Testament or its sources were originally written in Koine Greek. It is generally accepted by most scholars today that the New Testament of the Bible was written primarily, if not completely, in Koine or common Greek.[citation needed] Greek Primacy is asserted over and against Aramaic primacy and Hebrew Primacy."
Unfortunately I have no information on which language(s) the NT was originally written in, but I can tell you why I think that the Textus Receptus is "accurate and reliable."
Sometime in 2001, after I had begun to take an interest in the Bible (I had a NIV translation at the time), my Elohim showed me a very puzzling vision.
In the vision I and two good (atheist) friends of mine were on a quest for survival in the setting of man-made urban structures in different stages of decay. The vision ended with our exciting discovery, in the sub-basement of one of the structures, of an ancient treasure chest full of precious stones, gold, silver, and jewelry, which was the only thing of lasting value that could save us there.
At the time, I had no idea what the vision meant. It's meaning unfolded for me over the course of many years, through the physical manifestation of events from the vision in my own life, as well as answers to my prayers for clarification.
The urban structures symbolized the law and government of this country, and the treasure in the sub-basement symbolized the Word of God in the form of Incun. 1454.B5 in the Library of Congress and the Textus Receptus in the 1611 KJV. My Elohim showed me that I can rely on these for the knowledge which leads to salvation, freedom and everlasting life.
This does not mean that the Textus Receptus or Gutenberg Bible are the best translations. It just tells me that I can rely on them to be "a lamp unto my feet and a light unto my path" in spite of their well known shortcomings.