BMW does a great Silver, congrats...do they put in fresh pads for a CPO?An intermittent pull might be brake pads not seated in, or perhaps an alignment issue...does it pull more with hot wheels or cold? Are the tires new?

I doubt they bled the brakes and put new fluid in, but unless the brakes feel spongey I doubt there is air in the lines...have you tried braking with the Geartronic or applying the parking brake (does it brake all four or just the rear tires?) If no pull with Geartronic maybe that would narrow it down a bit.

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