Most people, however, operate in a somewhat narrower personality range. The key is to be able to identify your personal bounds of comfort. It's better known as being two-faced and in the business world it can be a real killer. Don't do it. But you should be aware of what your personality range is and be willing to move fluidly within that range to accommodate the personality of the individual with whom you are meeting.
Perfection is relative to the recipient.
As a side note, think about someone who you truly dislike. Extremes rarely enhance. If you put to practice this one technique, you will likely increase your chances of success dramatically, and not just in interviewing. Personality matching is a technique that you can use in virtually all areas of human communications.