Before I became a mortgage broker I was of the opinion that there was not that much to what they did.
Particularly when a mortgage broker did not follow through or explain why a process was not as smooth as it could have been.
After four years in the industry I have an altered view.
That being said we use a mortgage broker to optimise our lending. If you go to one bank you get what ever that bank offers. Different banks have different offerings.
So use a mortgage broker to find the loan most likely to suit your goals.