漢字そのままDS楽引辞典 - snap impressions
Weakness lies, simply put, in the fact that the intended audience is Japanese, not English-speaking gaijin. The translation of words like 神, kami, or 神道, shintou, sound to Western ears oddly like missionary cant. Kami is "God" and Shinto is not translated at all. Japanese know what these words mean, but perhaps may not have a clue what the Western analog might be. I'd suggest the English choices are clumsy, old-fashioned and embarassing, like reading those childish missionary approximations† to mature concepts forged over millenia in non-Western cultures. (Legge's translation of the I Ching comes to mind; no emails, please!)
On the other hand, the lexicon is reasonably current on decades-old words like "computer" and "global warming."
†By comparison, Andrew Nathaniel Nelson (who was a missionary, as well as a student of Japanese culture in the style Edwin O. Reischauer characterized as "geisha," meaning, gone native), translates 神 as "God, god, Allah" (impossible in today's America), and devotes two entire pages to the importance of this term in compound words.