The courses involved in pursuit of both of these degrees are very traditional. Meaning you take notes, read them, and regurgitate them for the exam. I'm not sure if that will help you in any way but it's out there.
Throughout my first year at Western, I've encountered many people who switched programs from BMOS to Psychology. They claim that it's because it's easier to get the higher marks in Psych, but again, it's very subjective and is only relevant if you plan on applying for the HBA.
However, the good news is that you don't really need to make up your mind until next March! There is ample room in your schedule to take your MOS courses along with a Psych elective so you can try them out and make a decision when you get a good grasp of both programs. (:
University of Western Ontario - 2015
AEO; Actuarial Science and Mathematics