The chemistry There are people who will travel a hundred miles to use a rabbi for whom they feel that chemistry. There are others locally who will travel a hundred miles to get away from the same rabbi. Very often, the situation blows up over a life cycle event. He won't officiate at a mixed marriage. The rabbi won't allow my non-Jewish relatives to have an honor at my son's Bar Mitsvah.
Most complaints come from the unaffiliated.
The affiliated vote with their feet and their dollars. The unaffiliated complain verbally. It helps justify their non-affiliation. There is always a grave danger in using second hand tales to evaluate a complex issues. This is particularly important when none of the actual participants can speak on their own behalf.