I took the OCA JP7 and unfortunately walked away with only a 55%.
This was after reading and noting Oracles Java Trail as well as a successfully completing a preparation course by Transcender. There were only two exams offered in the preparation course and 180 total questions. I scored a 73% after completing the Java Trail and Transcender flash cards and a 91% after completing the full course from Transcender.
I'll be using your approach for my next attempt!