I met with a group of actuaries within the IPM division of CSAA. The on-site interview took 3 hours total with 30mins for each interviewer. It was actually an enjoyable experience, though some of the "thought" questions invoked some real critical thinking so it's best to arrive on your "A" game. The host who brought me in was courteous and established a very welcoming environment. The interviews weren't too intimidating, but like with all interviews, you must remain focused and on edge to answer some thought provoking questions. Overall, the interviews went well, so you shouldn't be too worried about having a three hour long interview.