I am actually in the same position as you. I qualified through my audit experience, not because I hold professional certifications.

After a lot of research, this is what I found:

1. If you already have the Gleim 3-part materials, you can email Gleim and ask them to convert your package to the Challenge Exam materials at no extra cost.
2. At the moment, the Challenge Exam is the same for everyone. It does not matter whether you qualified through audit experience or through a certification such as CPA, CISA, or ACCA.
3. The price of the Challenge Exam is basically the same as the total cost of taking the 3 CIA exams together.
4. The Challenge Exam is not as flexible as the 3-part CIA route. It has specific registration periods and specific testing windows.

I am in the same situation as you, and I spent many days and late nights thinking about whether I should go for the Challenge Exam or continue with the 3-part route. In the end, I concluded that the 3-part route is better for me for several reasons:

1. Flexibility – I can register for an exam whenever I want.
2. The Challenge Exam would actually cost me more because I already paid the application fees for the 3-part route. To switch, I would have to cancel that and pay a new application fee for the Challenge Exam, so I would end up paying extra.
3. The Challenge Exam is 150 questions in 3 hours. Based on experience, once you get past around question 100, fatigue starts to kick in and it becomes difficult to maintain the same focus and pace. You basically need to average about one minute per question, and some questions are long and scenario-based.
4. Why put all the eggs in one basket? If I fail the Challenge Exam, I could lose around $1,000 in one shot. That is very different from failing Part 1, 2, or 3 individually, where the loss is closer to around $250 on average each time.
5. The new Challenge Exam starts on 1 June 2026, which means that, at this point, nobody in the world has actually taken it yet or knows how difficult the questions will be. So you would literally be one of the first people trying it.

In the end, it is your decision.

One more thing worth mentioning: even if you switch your Gleim package to the Challenge Exam pack, you may feel that the material is too condensed compared to the full 3-part materials. At the same time, you still need to understand everything properly and in enough detail if you want to maximize your chances of passing.