I got my ACE certification about 15 years ago, and have probably forgotten 90% of the info on the exam.
I was in my late teens when I took the exam, but that was the hardest Goddamn test I ever took... At the time at least, ACE and NASM were the most difficult certifications to require as compared to all the McCertifications available from the other online programs... I have no idea if ACE is still as respected as it was back in the day, but it used to carry some clout.