No disrespect to Rolf, who comes across as a very knowledgeable broker, but frankly I think most brokers are the "wrong" broker. And once you're with the wrong broker, you're stuck with them.
We have three loans with a broker at the moment. Our relationship with that broker broke down over his mismanagement of the third; our subsequent three went directly through the bank. Our personal banker looks after most things on the three brokered loans as a favour/goodwill thing, but he has limited visibility over them, so some things have to go to the broker. We are locked into that for the life of the loans. It is so bad that we have decided to refinance to get the broker out of the picture.
To make matters worse, (i) the broker decided to get out of the business and his service nosedived - no evening consults etc anymore, (ii) we moved so we now have to drive 80km to get to his office (whereas with our bank loans we can go to any branch if necessary), and (iii) when he did sell his practice, it went to a national company who now have all our private financial details that we would not have chosen to pass on. They also don't do evenings and are totally clueless about anything but the most basic PPOR lending.
Don't get me wrong - banks can suck too. But there are avenues if you need them. If one person handles it badly you can go to someone else, and they can see your information just fine. If a branch stuffs you around, there are complaint lines and media contacts and all sorts of people you can whinge to if necessary to get some pushthrough. The sheer size of the institution means you can work the system in a different way.
The only time I would ever use a broker again is if I had a specialist need such as a development and needed specific information about which players were friendly to that sort of lending. And even then, I'd ask here first.