... the amount of info coming from them would not be as great as the F/C/R or L/R surround
Try not to think of quanitity equaling quality. The QS4's are a perfect surround for that application. They sound great, don't let the size difference fool you.
From the first listening session I knew I'd made the right choice. I'd go as far to say they have sounded better than my QS8's in a few rooms/positions that they've been directly compared. Not all but enough times to make me hold onto them for future use.
