I recently passed the Salesforce Certified Platform Integration Architect exam. Before starting, I checked the official exam guide to see the section weightage. Design Integration Solutions and Build Solution (biggest chunks of the exam) were the hardest for me at first, picking the right integration pattern and API for a scenario took time to understand. Evaluate Current System Landscape and Maintain Integration were much easier once the core concepts clicked.
I was pretty lost on how to prep until a friend suggested ITExamsTopics. Checked their Facebook page first, got some useful tips, then tried the free demo on their website which helped a lot with the scenario-based questions. Went for their subscription after that and it covered the gaps well.
Passed comfortably on exam day. Happy to answer questions if anyone's prepping for this one.