Probably fairly accurate as to the quality of their normal Literature when translated.
One problem with this is that though a literal translation of a W.T Article may be an accurate one, what was written in English was often a strange way of expressing things to the speaker of another tongue, so their Translation work is not as good as that done by Professional Translators, well versed in the language being translated in to.
Of course it is a different matter when you look at their NWT Bible. This is a poor Bible Version in many respects, but is outright dishonest in many of its renderings, which they "bend" to support their Doctrines and Teachings, and to subtly exert "Mind Control" in some instances.
An analysis of these problems with their NWT Version can be found, and the verses in contention, on many Threads on here.