Maybe it's just a personal affection for this screen version of the Mika Waltari novel, or a fondness for things Egyptian (I grew up loving to visit the mummies in Boston's Museum of Fine Arts) but I think Maltin is a tad tough on this rather good film. The production values are great regarding color and cinematography, and it appears some effort went into historical authenticity (much of it from the novel, I'm sure). Purdom is admittedly a bit stiff in the lead role, but one can accept this as part of Sinuhe's character. Victor Mature is, well, Victor Mature. Peter Ustinov is a delight to watch in this type of role, which he always did so well and so wittily. Bella Darvi's performance as Nefer is classically camp, and I find even Michael Wilding's rather dry portrayal of Akenaten to have its own appeal.
The historical oddity of Akenaten's monotheism, a brief detour in ancient Egypt's theological history, is interesting, as is Akenaten himself, and well worth reading about; the religious wars portrayed here have a basis in fact.
An interesting footnote regarding Darvi, whose birth name was Bayla Wegier: she was a Polish emigre who producer Darryl Zanuck and his wife Violet took under their wing (I believe they may even have adopted her). Her screen name Darvi is formed from Zannuck's and his wife's first names. She continued her acting career in France, but never achieved great success and, after a rather unhappy life, died at her own hand in 1971.
Altogether this is an interesting film and enjoyable to watch for the visual values alone. American Movie Classics shows this occasionally in letterbox, which is essential to capturing the scope and sweep of the story.