Bottom line: You need to know what you're doing
Review: Grammar Expert Plus means well and it does find flaws that other writing programs miss. But the software has several flaws that make Grammar Expert Plus less useful for the novice writer than other software.
The grammar checker looks for thousands of common grammatical errors, syntax errors, misused words, wordy phrases, subject-verb disagreements, misuses of its and it's, your and you're, etc.
But unlike other software, such as StyleWriter, WordDog, ClearEdits,
and Whitesmoke, Grammar Expert Plus does not integrate into or become
part of any other application (for example, Word). Rather, Grammar Expert Plus
is a "stand alone" program. This means you must copy and paste text
from your word application into the grammar checker. This not only
takes time, but also can cause formatting problems. For example, when
we copied formatted em-dashes from Word into Grammar Expert Plus, the em-dashes became hyphens. The makers of Grammar Expert Plus acknowledge, in the user manual, the problem of lost formatting.
The makers of Grammar Expert Plus are
very honest and upfront about the software's limitations. Some of these
limitations apply to all grammar checkers generally; but some of the
limitations apply specifically to Grammar Expert Plus. For example, the makers of the software have chosen to find "false positives" in preference to missing possible errors. At first, this approach made sense to us. But as we continued to use the software, the "errors" that Grammar Expert Plus found, which weren't really errors, began to annoy us. This is despite a nifty little feature that lets users tell Grammar Expert Plus how hard the software should try to find errors (by adjusting the software's "confidence level").
Some of Grammar Expert Plus's suggestions were truly bizarre. For example, the software said we should consider changing "given" to "givens" and "can be" to "cans be". When we began a sentence with "Born in the USA," the software suggested we consider replacing "Born" with "Born" or "Born" (that is, the two suggested alternatives were the same as the original). The software also sometimes inserted rogue spaces.
While these glitches may be problems to do with coding, Grammar Expert Plus made some other suggestions that we would quibble with. For example, the software suggested changing a sentence that began with "But" to "However" or "Nevertheless". This seems like an old-fashioned suggestion. The trend is away from multi-syllabic words to shorter-sounding words. Also, Grammar Expert Plus rightly said that "and/or" should be avoided; but then added "except in legal text". But "and/or" is also often over-used by lawyers where "and" or "or" would do.
Overall, Grammar Expert Plus does have a use: professional writers who know what they're doing, and who can properly assess the software's suggestions, could use the software to find flaws that other software may miss. But someone who did not know English well might get lulled into making a change that could potentially weaken their writing. The $59 asking price might be better spent on Editor or one of the other software titles around the same price.