The Gesta Francorum is not only a pivotal source for professional scholars of the crusades, but also one that is relatively short and accessible to students, making it a vital resource for teaching as well as scholarship. As a result, Rosalind Hill's classic edition and translation has become a standard part of any college or university library and excerpts of the translated Gesta can be found in multiple sourcebooks, especially those concerned with the crusades. 
Given the centrality of the Gesta for teaching as well as scholarship, and given the amount of scholarship done on the text since Hill's edition was published in 1979, in theory a new translation and edition would be very welcome. That said, given the quality of Hill's work and the high number of useful excerpts already in place in sourcebooks, it seems to me that such a new edition/translation would need to excel, i.e. significantly improve upon Hill's work, in three areas:
1. Quality of translation.
2. Quality of editorial work and writing, especially in the Introduction.
3. Price and availability.
Unfortunately, as I discuss further below, Nirmal Dass's translation only excels in terms of price and availability.
The most important criterion for evaluating a new translation is, of course, the quality of the translation itself. Dass himself believes that his translation is the main strength of his work, explicitly criticizing Hill and other past translators: "the archaisms prevalent in the previous two English translations have been avoided, especially in the case of Hill, who takes excessive and needless liberties with the original" (22). Dass further explains these liberties in a note, saying "the most notorious of which is linking the author closely with Bohemond by adding what is missing in the original. For example, she consistently gives 'my lord Bohemond,' when the original simply states 'lord Bohemond'" (123).
Dass fails to provide a citation for Hill's repeated insertions linking the author with Bohemond. However, I decided to look at the betrayal of Antioch (which heavily features Bohemond), and was able to find the passage at the very end of the eighth book (69). The Latin reads "et tulerunt ante Boamundi presentiam," which Hill translates as "they took to my lord Bohemond."  Certainly this is not a straight translation; Hill has indeed inserted "my lord." That said, this is hardly scandalous, nor does it disqualify Hill's translation. After all, if one reads through the entire eighth book, although Bohemond is referred to repeatedly on virtually every page, all of those references are translated completely literally by Hill, with no "my lord" added. Furthermore, one can immediately spot the issue because the Latin text is on the facing page. In short, Dass's complaints about Hill's translation are unconvincing.
Dass's own translation of the words of the text itself is fine, in my view, and he is sometimes (though not always) more true to the literal translation of the Latin than Hill. To take one example passage, let's look at the description of the destruction of Jerusalem in the ninth book. Where Hill translates "dignatus est pro nobis sufferre" as "deigned to suffer for us,"  Dass translates it as "had consented to suffer" (and omits to translate "pro nobis") (103). Later in the same passage, Hill translates "fortiter" as "bravely" while Dass chooses "valiantly"; Hill translates "milites" as "knights," Dass opts for "warriors." While Hill does streamline and lightly consolidate the passage, Dass keeps the rhythm and structure of the original with all of its repetitive conjunctions, which I do personally appreciate.
However, I am less appreciative of Dass's subheadings throughout each book, which impose meaning upon the original text of the Gesta. These anachronistic subheadings include "Pope Urban II preaches the First Crusade," "The People's Crusade," "In Praise of Turkish Valor," and "Bohemond Makes a Friend" (25, 26, 43, 66). If Dass were to alert his reader that these subheadings were his own additions, that would be one thing, but he does not do so. Indeed, on the contrary, he explicitly states that "it is the intent of this translation to not allow editorial outlook to skewer or color what the Gesta has to say" (22). This assertion seems to contradict the use of subheadings, and may well lead readers to believe that the subheadings are part of the Gesta, when they are not.
Turning to the second criterion noted at the beginning of this review, namely the editorial contribution of the work, more substantial problems are immediately apparent. To begin with, Dass has clearly written for a non-specialist audience, indeed for an audience unfamiliar with the crusades. This is not only acceptable, but laudable, especially for a translated work. However, writing for a non-specialist audience does not excuse an editor from serious scholarship. In this situation, the editor's job is to do the scholarship as a specialist and leave a detailed trail for serious students to follow, all while finding a way to communicate effectively to non-specialists. It is not clear that Dass has, in fact, done the scholarship; he may have done, but it is not readily apparent from his notes. For example, he cites Jay Rubenstein's 2005 article, but does not give information on any of the other main studies of the Gesta (120).  This is the pattern for virtually all of his notes in the Introduction, which mostly reference one main text and leave it at that.
Furthermore, the general history of the period is frequently grossly simplified, to the point of blatant inaccuracy. To give just one example, Dass states that "by the time Urban II became pope in 1088, the Church was a tightly organized institution, self-sustaining and independent, that could marshal, direct, and control a unified response from its faithful" (16). If only Pope Gregory VII had known this, when the dire aftermath of his conflict with Henry IV of Germany, especially the fateful decision to call on the Normans, forced him to withdraw from Rome before his death in 1085! Sadly, the lack of full references and inaccurate background history make this introduction unhelpful and frankly unacceptable, even for undergraduates.
Finally, Dass uses this introduction to launch his own theory about the origins of the Gesta. He notes that four names appear at the end of one twelfth-century manuscript. These names, he suggests, are those of the authors (6). The evidence provided for this is inconclusive at best; he simply notes that the handwriting is from "the first half of the twelfth century, the very era of the Gesta's composition." He also does not tell us what other scholars have made of these names or how they have explained them, implying (though not explicitly claiming) that he is the first to have spotted them. Nor does he tell us anything further about the given names. The casual inclusion of this kind of dramatic and unsupported "origins theory" is oddly out of place, to say the least.
This leaves us with the pricing and availability of the book. And here, certainly, Dass's translation has a clear advantage. The text is slim and light, and one can readily acquire a paperback copy for $24.95 or an e-copy for just over $16. I can imagine--and understand--some instructors choosing to use Dass's translation for these characteristics alone. That said, to avoid having to un-teach portions of the introduction, I will not be using this translation in my own undergraduate classes.
1. Rosalind Hill, ed. and trans., The Deeds of the Franks and the other Pilgrims to Jerusalem (Edinburgh and London: Thomas Nelson and Sons, 1962). For examples of crusade readers, see Edward Peters, ed., The First Crusade: The Chronicle of Fulcher of Chartres and Other Source Materials, 2nd edition (Philadelphia, University of Pennsylvania Press, 1998) or S. J. Allen and Emilie Amt, eds., The Crusades: A Reader, (Toronto: University of Toronto Press, 2003).
2. Hill, 48.
3. Full passage in Latin: Appropinquante autem hora scilicet in qua Dominus noster Iesus Christus dignatus est pro nobis sufferre patibulum crucis, nostri milites fortiter pugnabant in castello, videlicet dux Godefridus, et comes Eustachius frater eius. Tunc ascendit quidam miles ex nostris Laetholdus nomine super murum urbis. Mox vero ut ascendit, omnes defensores civitatis fugerunt per muros et per civitatem, nostrique subsecuti persequebantur eos occidendo et detruncando usque ad Templum Salomonis. Ibique talis occisio fuit, ut nostri in sanguine illorum pedes usque ad cavillas mitterent. (Hill, 90-1)
4. Dass rightly cites Jay Rubeinstein, "What is the Gesta Francorum and who was Peter Tudebode?," Revue Mabillon 16 (2005), 179-204. But see also John France, "The anonymous Gesta Francorum and the Historia Francorum qui ceperunt Iherusalem of Raymond of Aguilers and the Historia de Hierosolymitano itinere of Peter Tudebode: An analysis of the textual relationship between primary sources for the First Crusade," in J. France and W. Zajac, eds., The Crusades and their Sources: Essays presented to Bernard Hamilton (Aldershot: Ashgate, 1998), 39-69; France, "The use of the anonymous Gesta Francorum in the early twelfth-century sources for the First Crusade," in A. Murray, ed., From Clermont to Jerusalem: The Crusades and Crusader Societies (Turnhout: Brepols, 1998), 29-42; Colin Morris, "The Gesta Francorum as Narrative History," Reading Medieval Studies 19 (1993), 55-72.