The third edition of Stephanus' Greek New Testament (ΤΗC ΚΑΙΝΗC ΔΙΑΘΗΚΗC ΑΠΑΝΤΑ: Paris, 1550), known as the editio regia, is held in high regard in English Protestantism. It was this text which underlay the English translation (by W. Whittingham and others) published in Geneva in 1557 that greatly influenced the Geneva Bible published three years later. In effect, Stephanus' edition was the Textus Receptus of the Greek New Testament for over three hundred years.
In his description of Stephanus' third edition of the Greek New Testament (1550) Elliott also includes a helpful table to identify the fifteen witnesses cited in the margin of the edition. Elliott also gives examples of a number of inaccuracies in the edition, some of which were noted already by Wetstein 1730. In this connection he points out that Scrivener had noticed that Codex Bezae was sometimes only loosely cited. I think this particular problem applies not only to Bezae in Stephanus' edition. In fact, in Jude I know that there are not only errors in the four or five MSS that Stephen cited there, but many interesting and significant variants in those MSS are not indicated at all.
Elliott further says that "modern readers may find it useful to examine (with care) Stephanus’ apparatus for access to and information on the readings of the now lost manuscripts cited (8a-10p, 3r, and perhaps 50a-8p)." In my own work on Jude I did that with 8a - a lost MS that could be accessed only through Stephanus' apparatus. I could conclude that this now lost MS shared most of its readings with 1846. Elliott also suggests that Stephanus' edition could be consulted for readings not found in modern editions.