Re: Trust Office
It really all depends on your definition of "usable". If that includes /quality/ printed output and you're picky about kerning, etc. then yes marginally usable is an appropriate phrase. If that includes managing /really/ big documents, then yes marginally usable is an appropriate phrase (there's always some bugger who refuses to use styles).
As for competitors, I remember when $work switched from WordPerfect to Word (over the loud and furious objections from those who worked with documents the most) - there wasn't a consideration of any of the competitors.