All extant manuscripts of Propertius derive from a lost manuscript that is labeled by the Greek letter omega.
Let the reader compare Goold's text with Barber's Oxford text and look at Goold's apparatus criticus, at the bottom of each page. He will see that Goold constantly differs from Barber by printing conjectures instead of the reading of omega. As far as I can tell, in every case, the reading provided by omega is intelligible, and in nearly every case appropriate.
Goold's basic criterion for emendation was plainly to make the meaning of the Latin simpler and more obvious. He thus reversed the most basic principle of textual criticism: lectio difficilior potior (the more difficult reading is better). The reason for this principle is clear: a scribe is more likely to change (whether consciously or unconsciously) a phrase that he finds difficult to understand into one that is easier to understand rather than vice versa. This principle is especially true of Propertius, whose style is compressed, elliptical, oblique, allusive, and saltatory. ("Saltatory" is an adjective coined by Propertian scholars, from the Latin noun saltus, which means a leap/jump.)
As for Goold's translation, it is often ludicrously wrong, even for the Latin text he prints (let alone for what Propertius probably wrote). To take one example, in I.3.44, his translation of externo in amore as "in unmarried love" is both blatantly inappropriate to its context and violates the entire ethos of the Cynthia cycle.
My recommendation to those who know any Latin is W. A. Camps' edition of each of Propertius' four books.
I wrote the review above before I had access to Heyforth's 2007 revision of Barber's Oxford text. I had decided that if I found that Heyforth agreed with Goold, I would withdraw this review. Heyforth praises Goold in his Preface (page lxi) for "set[ting] a strong case for emendation and transposition" and says about his own edition (page lxv), "This may be thought a radical edition ... But I suspect that there are ... far more places where we need to deviate from the MS [manuscript] tradition than to return to it."
Nevertheless, Heyforth consistently agrees with Barber's MS-based text in preference to Goold's emendation-based text (e.g., I.1.16 (preces/fides); I.1.19 (fallacia/pellacia); I.3.45 (lapsam/lassam).
Goold is like the editor of Milton's Paradise Lost who changed "darkness visible" (I.63) to "darkness invisible" because darkness cannot be visible.