In some states, there is a mandatory reporting to drivers license bureaus, but that is the only negative I can think of, having a dx on your medical records. remember that your medical records are strictly protected for privacy.
Having a dx on paper can be really valuable, especially if in the future you are less able to pursue paperwork for disability, for consideration under the Americans With Disabilities Act (school, work, insurance), or to get your prescriptions. Many insurers make extraordinary documentation demands, to keep filling a nuvigil scrip.
As for the sleep study for dx, that is something that health care providers will tell you with a straight face, is NECESSARY for diagnosis. However, the medical standards for dx include several other criteria and sorts of tests, and sleep labs are notoriously underregulated and undependable.
I have some research on these if you wish to see it. It is shocking to think how many of us are hamstrung by the sleep testing industry and insurers. I am not able to get meds or even a tiny replacement part for a cpap mask, without a CURRENT sleep test (which would be my 13th!), which would require referrals to specialists, and traveling to Phoenix, and which the insurer will NOT pay for.
Good luck, I am not sure how you can discreetly find out about keeping your drivers license. But my signed-and-sealed dx is like gold to me.
email me anytime, or post here. These are wonderful people who understand.