If your brand new Mac had issues you should have returned it when it was brand new and inside the return window. You no loner have a brand new Mac - you have a used Mac under warranty. Apple policy states you have to return it 3 TIME FOR THE SAME ISSUE then they will replace it. In your current position you should allow them to fix it and move on.
In regards your analogy, if you brought a car back to the lot 15 days later and there was a warranty issue and you demanded a new car they would laugh at you. They have to fix it.
Good luck.
In regards your analogy, if you brought a car back to the lot 15 days later and there was a warranty issue and you demanded a new car they would laugh at you. They have to fix it.
Good luck.