Was at an Aston owners pub night last week and someone said the same thing on their '19 Vantage test drive about the brakes. I bet one with 5K miles will be more like you were expecting.

 

I had a DB11 while my car was in service and it too had "grabby brakes". I agree with the other poster that they are very different from my 2016 911 turbo. In the 911 the brakes are more progressive in that the amount of braking is linear with how far you push the pedal. In the Aston, initially there seems to be little stopping then all of a sudden the brakes grab. That being said, the more I drive these cars the more I am getting used to it.

 

I spent the weekend with the New Vantage. This had the cast iron brakes on it and just over 1,000 miles logged. The brakes are definitely grabby, inching forward is an art unless you like some minor whiplash (jk, it's not quite that bad). I did get more use to easing on and off the brakes by the end of the weekend, but it would take some getting use to.

The squeaking was very apparent and very irritating. It made me feel that I was driving an old beater that had worked through the brake pads. Perhaps I'm being a little vain, but I also found it a tad embarrassing. The Vantage gets a lot of looks and coming to a stop at a traffic light while your car goes "screeeeeech" is not exactly my first choice. Above it said it's the compound they use ... how would you solve this problem?

 

Take it to the dealer and demand that they change the pads or something until it stops... that is completely unacceptable