Doug Reid said:
"Back in the day ( here we go young-uns ) we had to read the study material and hope for the best...no test prep questions to memorize on the computer."
When preparing for my PPL written, I signed up for a Commercial ground school taught by a pair of recent ATP's. They wrote their own handouts and tests. 3/4 of the way through, I was ready for the flight test, so took the written. I had been self studying for months prior, and found few questions on the written that I did not understand
Score, high 80's, and the review my flight instructor gave me covering the areas that I missed were covered in the ground school after the FAA test. I scored nearly 100% on the school exam.
There were some very tricky questions, but if I carefully puzzled out the intent, they made sense.
Later, for my Commercial and Instrument, I had the Piper training materials, self study, and took both on the same day, passed with a score in the high 80's.
A friend took the Commercial at the same time, failed, and complained about the confusing questions. He used the same study materials as I did.
The test is not perfect, never was, but if you know and understand the material, I suspect that you will get at least a passing grade.
My orals went very well, as I had learned, not memorized the material, and the DPE's asked practical questions.