Jack it up & prop the pedal down to make sure you are getting braking on all the wheels. Although it should show up on the bleeding process it may have a pinched brake tube or swollen brake hose. It doesn't sound like a problem with the master cyl. The linings do require a wear in to get full contact with the drum. Some of the linings we get know are really crudy. They have taken out the asbestos & who knows what they are using.
This is a tough one.
