I've tried reading David Weber (in the 1632 series mainly) and discovered an allergy to his writing style. It's the whole "stop the plot so I can exposit at you" thing and also some clunky sentences. I've read the entire Vorkosiverse* and most of CJ Cherryh's ouvre, and a lot of LeGuin (I think the Hainish books count as space opera). I've heard good things about our hostess' Jenny Casey books, though I've not read them.
*Except Captain Vorpatril's Alliance, though that should be remedied soon