Pros
Relaxed and constructive office environment. Personal cubicle, WFH if management allows it (case-by case basis). Vast networking opportunities. Very comfortable hours (8AM-3:30PM, Mon-Fri) with lenience if you would like to take unpaid leave (depending on your manager).
Cons
Regimented, heavy adherence to processes and documentation makes revising or automating tedious manual processes difficult. Large technical and linguistic learning curve (OPG has a LOT of acronyms for everything), but this is manageable if you keep your reference resources organized. Work you are assigned to over PEY Internship does not necessarily reflect your academic focus (I was in electrical, but most of my workload involved programming and scheduling work; be prepared to mould yourself to what is required of you).