I'm not quite sure how to place "The New Complete Works of Josephus" (Kregel Academic & Professional, 1999) among other editions of Josephus that are available.
This work is a "revised" version of Whiston's 1737 translation, which has been "corrected" to an unknown degree by Paul L. Maier.
Besides Josephus' writings, the book includes 7 "dissertations" on the text by Whiston such as "The testimonies of Josephus concerning Jesus Christ, John the Baptist, and James the Just, vindicated". These along with the footnotes reveal a translator anxious to defend the authenticity of his source text(s), the historical accuracy of Josephus, the correspondence of Josephus's accounts with the Old and New Testament, etc.
Whiston seems to have a vested interest in Josephus as supporting and supplementing various Biblical accounts. He definitely comments upon the work from a Christian (he was actually an Arian) rather than a purely critical perspective. However, I see no reason at this time to believe this infects his translation with bias.
Assuming that "Complete Works" has been completely corrected, it's greatest failing is being very difficult to read. Apparently, Whiston had something against periods, but really loved semicolons. Many a sentence runs on and on to paragraph length. The syntax is tortuous.
The same publisher has two other editions of Josephus that are very different from Complete Works, yet seem very similar to each other. These are "Essential Works" (Josephus: The Essential Works) and "Essential Writings" (Josephus: The Essential Writings). Both are current editions using a translation by Paul L. Maier.
The following is a sample of Maier's new translation followed by Whiston's. The text corresponds to Loeb Bk. VI, Ch. 14, 374-378
From "Josephus: The Essential Writings", Kregel, 1990, ISBN 0825429641 (Maier translation)
The next day, when the Philistines came to strip the bodies of the slain, they found those of Saul and his sons, and they cut off their heads and impaled their bodies on the walls of Bethshan. But when the Israelites of Jabesh-Gilead learned about this mutilation, the bravest of them marched all night to Bethshan, removed the bodies of Saul and his sons, and carried them to Jabesh, where they buried them. The enemy was either not able or not bold enough to stop them, because of their great courage.
Saul came to this end, as Samuel had predicted, because of his disobedience regarding the Amalekites and his destruction of the high priest and his family. He reigned eighteen years during the lifetime of Samuel, and 22 more after his death.
From "The New Complete Works of Josephus", Kregel, 1999, ISBN 0825429242 ("corrected" Whiston translation)
On the next day, when the Philistines came to strip their enemies that were killed, they got the bodies of Saul and of his sons, and stripped them, and cut off their heads; and they sent messengers all about their country, to acquaint them that their enemies were fallen; and they dedicated their armor in the temple of Astarte, but hung their bodies on crosses at the walls of the city Beth Shan, which is now called Scythopolis. But when the inhabitants of Jabesh Gilead heard that they had dismembered the dead bodies of Saul and of his sons, they deemed it so horrid a thing to overlook this barbarity, and to suffer them to be without funeral rites, that the most courageous and hardy among them (and indeed that city had in it men that were very stout both in body and mind) journeyed all night, and came to Beth Shan, and approached the enemy's wall, and taking down the bodies of Saul and of his sons they caried them to Jabesh, while the enemy was not able enough or bold enough to hinder them, because of their great courage. So the people of Jabesh all wept and buried their bodies in the best place of their country, which was named Aroura; and they observed a public mourning for them seven days, with their wives and children, beating their breasts, and lamenting the king and his sons, without either tasting meat or drink [until evening].
To this his end did Saul come, according to the prophecy of Samuel, because he disobeyed the commands of God about the Amalekites, and on the account of his destroying the family of Ahimelech the high priest, with Ahimelech himself, and the city of the high priests. Now Saul when he had reigned eighteen years while Samuel was alive, and after his death two [and twenty], ended his life in this manner.
Even granting that the Maier translation is abridged, you can see that the Whiston translation suffers pitifully where readability is concerned.
If you're still with me I'd say this. If you can afford it and need the complete works, buy the Loeb editions. I can't personally vouch for them, but in the introduction to "Complete Works" Maier himself states that those represent the "best English translation".
If you don't need each and every line and want text you can actually parse, perhaps you should buy "Essential Works" or "Essential Writings". I can't tell you which, since I don't have them and I'm mystified as to what the difference might be. Of course, there are other translations and editions from other publishers of repute that are certainly comparable in readability.
If you need (or want) every line for a very economical price, "Complete Works" will do.
Good luck reading it.