Long time lurker, first time poster. Just wanted to share my .02 about the OAR I just took a few hours ago.
Math - Gouges and study guides on here were extremely helpful. Nothing that I didn't see here that I didn't expect. Adaptive test only gave me about 12-14 questions, can't remember the exact number. Was hoping for some logs and matrices, but got hit with a real stunner... Binary Code. While it was only one question, it knocked me for a loop and lost some quality time. Gave you the number for 2 in base 2, and explained it less than sufficiently. The question then asked how to represent an addition of two numbers in Base 4. Apologies if I didn't explain that completely clear, its still boggling my mind. Other than that, multi-dice probabilities, distance, etc.
Reading - Like most have said on here, very heavy on Naval terminology/manual interpretation. Occasional butterfly/bird/non-Naval type stimulus. Nothing that I didn't see on the ASTB example documents.
Mechanical - Most likely bombed. No questions on string tension, pulley's, pendulums, fulcrums. Very electrical based, lots of questions regarding amperage/voltage/ohms. I had practiced quite well on this section, and had known most of the information from common sense. Could not get me by on this test. Disappointed to say the least with this section.
Overall - OAR of 51. Did not take the remaining sections, as I am past the age for aviation. Pretty confident I did beyond my expectations for Math and Reading, but should have looked more into the Mechanical specifically electrical. With work, studied about an hour to 1.5. May re-test in 90 days to improve on mechanical.
The information that I have found in this forum was invaluable for mustering up the courage to take the exam, let alone the information on the test. Thank you for all the help!