I went through 3 days of interviews with at least 6 people and then was required to put a presentation together. It was overkill by the 3rd time, I felt very uncomfortable by that point trying to sell myself into a mediocre position I was highly over qualified for but thought I would enjoy. It was extremely disappointing to have been put through so much time and effort into the interviews only to be rejected once I sent a follow up email to them. In my personal opinion, you really know after the 1st or 2nd interview. The process took weeks. Far too long of a process. Some of the interviewers really gave off a "I'm better then you vibe."