PPI books and online cafe problems = harder than AM questions and not completely in scope of exam (simplified seismic design and direct masonry design are examples of ppi questions from their online database that I feel are out of scope)
The PPI book that was a waste imo was the solved structural Engineering problems one and the California seismic books. Get the Hiner book instead.
The PPI steel book is pretty useful for vertical practife...similar to the concrete PPI book. The examples in the steel one are close to SE level the examples in the concrete one are ok. The practice problems in the concrete one are over tuned imo.
The only ppi book besides serm that is really good is their 16 hour sample exam that one felt spot on in terms of scope and difficulty.
SEAOC books -- vol1 excellent for learning and similar to AM questions in some cases, vol 2,3,4 are good for afternoon references.
Stephen Hiner Seismic workbook - on par with SE lateral seismic, solid resource
AEI course material tuned ideally for SE
David Connors bridge book - some questions felt more than 6 mins as is likely the case with its intended target audience, but his 80 questions combined with AEI plus a few Caltrans pdfs and you're set
NCEES sample is tuned easy however it does provide useful insight to the distribution of questions and qualitative only type questions
Not to completley dismiss the ncees practice think of it this way... you can take any of their questions and add one to two more intermediate steps and itll feel appropriate or do the opposite see if you can handle the 40 questions in 3 hours.
And I'll keep waiving the flag for anything written by David Fanella.