Only one good text
According to modern theologians the King James Bible has been so corrupted by copying errors that it really can no longer be used for theological purposes which is why they made a new Greek text to correct the errors in the King James Bible. The problem is that the texts they use are also copies a few hundred years removed from the originals so they too have errors. So you have codices, which contain copying errors according to their reasoning being used to correct another text that supposedly has more copying errors. There is no rational basis for doing this because it means the Greek texts they use are also ineligible for translation purposes for the same reason the King James Greek is ineligible for translation purposes. They are all copies of earlier documents and according to their reasonings would have copyist errors in them.
There is one text that has an unbroken lineage of over nearly 2000 years and uses the language the apostles would have used to write down things. They would not have used Greek as it was detested as it was not Jewish but used Aramaic mainly. This text is the Syriac Peshita which has unbroken lineage so copying errors would have been easily detected from other texts they had that were being used at that time. In fact there are very little differences in the codices we have even though it has been copied for nearly 2000 years.
Because of the accuracy of the text and it showing the errors in the modern Greek, theologians have had to come up for a reason to say that it is not reliable. They say it was altered in the 4th Century so that it is not as accurate as the 4th Century codices they use. There is no evidence of this alteration ever happening (and if you find it you will be famous) but it suits their purposes to lie so they do. It is not the only time one of them has been caught in a lie.
The other real problem modern theologians have is that the four texts they use are all proven forgeries. You will not hear much of that from main stream theologians as their it too much money and reputations involved.