I was recently diagnosed from a neuro-psych. Similar process of many hours of testing (~5h). My friend was also diagnosed recently from a psychiatrist through question answer, but no formal cognitive evaluation measure. The amount of clarity I got from the neuro-psych in terms of cognitive function and my specific circumstances was significantly more helpful than what my friend got from the psychiatrist.
After all the formal testing, I was given a thorough 17 page report including a breakdown of each aspect of cognitive functioning, any applicable disorders (with recommendation for therapy to investigate further and confirm), next steps, and treatment and coping mechanism recommendations. My friend was given a broad diagnosis of unspecified ADHD with no additional information.
If you are able to afford the neuropsych eval, it is well worth it.
An important distinction is that a neuropsych eval focuses on cognitive function. It works for ADHD because it is a cognitive function disorder and will show directly in testing as a deficiency in executive function (plus possibly other stuff, I'm not an expert). They also do the psych eval tests but they can normally point to broad things that you will need therapy to dig into.