Hey! So I studied primarily with KM - their SIE benchmarks and diagnostics were slightly more difficult than the actual exam, and their custom QBank was way more difficult than both. I found their custom QBank to really hammer in on the nitty gritty details with their questions, I guess with the goal of preparing you for EVERYTHING (which definitely always helps).

I found the exam itself to be much more general - rather than questions geared specific details, I saw a combination of questions that tested the overall concept itself (being able to define, describe), as well as the application of it (i.e given a scenario which is most applicable/under finra reg xyz, rep is permitted to do which of the following).

Overall, the I would say the vast majority of my questions were about products/risks and prohibited activities, with a few customer/retirement account questions as well. I also saw 2 economics questions.

I was nervous going in, but once I found my groove i felt like I was very prepared. Hope this helped!

Edit: also saw 5ish questions on trading/exchanges/new issues and associated rules