I have had two interviews. Both were very different from each other. In the first, it was extremely well structures, and in the second it was more of a conversation -- the interviewer almost seemed like they were trying to sell me the job at times. The organizational structure allows a good deal of autonomoy for each researcher, so this is probably a factor behind interviews being varried. If you interview, the only way to get some preparation is to know a bit about who is interviewing you.

It was an easy great experience, you just have to have high Emotional intelligence and connect with the employees. Bring in some experience with the research field but an overall easy interview.