Finding a good client service representative is difficult. In my experience, they are either very good and helpful or not helpful at all. And except for certain situations, one usually doesn't get to choose.
The major problem I see is that because client service representatives are looking out for the interests of their company, they don't give advice that's in the best interests of the client. So let's say that a client is better off using one service than another, but the other option will get the company more money, the representative usually opts to do what's best for the company.
Of course, I expect a representative to serve the interest of the company he or she is working for. But it is possible to find a balance between the two. One can and should also look out for the client's interests.