LilBro

this is the first time i ever had a brake job. Well all four, last time i just had the fronts done. When i am like rolling slowly and i press the brakes i hear a weird like metal noise. I am confident it is coming from the rear brakes cuz when i do the same at a slow roll and lift the e-brake i get the same noise. i have a few hundred miles on the brakes now and dealer told me they are probably breaking in...is this true or did they just do a shit job???? keep in mind when they do the brakes on my car, they give new calibers and everything....

thanks in advance for the help....