While I have high hopes for Harris, I think we need to pump the brakes on everyone trashing Branch,
5.5 sacks isn't any great number, but when you remember he didn't start the first 5 games of the season that number looks a bit better. Last year's pace would have had him at 8 or 9 sacks, which is nice for your second best pass rusher. Branch was also decent against the run, and had great energy when he was on the field, one of those guys that gets the other players pumped up.
Ultimately, I would love to see Harris take the starting job away from Branch, but that would mean that Harris would be playing at a very high level, not that Branch is a bum.