I haven't had a chance to test my luck yet, but I feel strongly about not answering questions I don't have to answer when pulled over, and never consenting to a search.
I have absolutely nothing illegal in my car, ever. I speed pretty much always, but I don't drive drunk or anything else. I'm also extremely diligent about following all other traffic laws other than speed. Always signal, always come to a complete stop. Don't tailgate. Never use my phone while my car is in motion.
But if a cop asked me why I was going so fast I would respond "I was driving at a comfortable speed that I felt was safe." If asked where I was going or where I was coming from "With all due respect, sir, I'm not interested in discussing my itinerary." If asked to allow them to search my car "I do not consent to searches." Any other chit chat, "I prefer to not answer any questions not directly related to the reason I was stopped."
I've never gotten a warning, so I don't have any expectation that I'd smooze my way out of a ticket by being chummy with the cop. I just don't have that type of personality. I'd be absolutely reasonable and respectful, switched into enlisted military member talking to a senior officer mode. And if given a direct order to do something I'd do it. If the officer insisted on searching my vehicle I'd comply while making it clear that it was not with my consent.