Skeletons in closets
You ask some good questions. I don't recall how long it took to get my file.
PRIA wasn't around when I was in the job market, but companies could always obtain FAA records. Mesa used to send employment verification forms to one's past employers, so I suspect the net effect for both was the same.
I haven't a clue if companies have access to some all-knowing database or NCIC or anything like that to verify applicants' claims. Job applications are construed as legal documents and if a company uncovers information about you on a background check that differs from what is on the app, you're as good as out. Even inadvertant omissions can cause problems. Your information has to be consistent. Of course, there is more than one side to every story.
Anything on an app is fair game. Therefore, I believe that one should acquire any records about yourself that others can find, i.e. driving records, FAA records, especially concerning violations, accidents and incidents, credit reports (some states, such as Colorado, let you obtain credit reports for free), everything. All paper that can be found. In other words, do a background check on yourself. I had a friend who was having trouble finding work after being let go and who suspected that former employers were badmouthing him. He asked me to call his former employers and pretend I was a prospective employer wanting to hire him. One ex-employer indeed was saying bad and untrue things about him.
The idea is to be loaded for bear. You'll know what others can find out, which will help you answer application questions and prepare truthful and accurate responses to interview questions.
I've formed the belief that aviation companies care only about three basic things: (1) Do we like the applicant personally; (2) Is the applicant trainable; (3) Is the applicant qualified. Sure, the airlines all want saints and love pristine records. I fail on both counts, I guess. I've busted rides, I've had less-than-perfect job separations and I've had traffic tickets. I suspect most other people have as well. The important thing is to show one can learn from mistakes and avoid them in the future.
Hope that helps. Good luck with your job search.