Courteous interaction: you did not feel that you are being done a favor. Interviewers had a short notice, so they were not as prepared as they would have liked to be. There is enormous talent there, so the discussions even without preparation were great. The discussions gave a good idea about what was involved in the work, what were the goals and challenges.
Unfortunate part was that the company did not back to me in time to consider them in my decision making. By the time they wanted to have a final interview to make the offer, I was already working at another San Diego company for about a week and a half.