Unfortunately, I don’t know what ST series exams are. However, I do believe that it is always good to pass as many exams as possible before you take a job. I had passed 4 of the 9 actuarial exams in the US at the end of my third year in university. I was fully qualified after my second year on the job at age 24. That gave me a huge head start in my career. I have heard people say that passing too many exams is not good because it makes you more expensive. I disagree. I believe moving through the exams rapidly demonstrates a strong ability and a strong desire to be an actuary.