Definitely at that dose! I started with a 5 mg tolerance test at 80 kg, was at 15 mg for a while and slowly worked up to 50 mg over 9 months.
How it affected me is quite different, but just as stunning! Especially in the first 2 - 3 months, I was in a constant state of euphoria; it felt like a recreational stimulant drug you'd get at a rave. But the main ADHD symptom that was gone immediately was that I couldn't get myself to start on a task.
Other advantages came slowly and more subtle at higher doses. It's still mostly that I finally do what needs to be done. But I do that in a very confused, easily distracted way. I'm basically Joe Biden on speed.
Very much life changing, as the anxiety from missed deadlines and built-up problems is gone.
I was so happy when I started with meds, just for the 4 hours before I crashed. Got more done than in a whole day.
Then the doc explained that crashing is not a must: I just have to eat by clock and calorie count rather than relying on appetite, not exercise / cleaning-frenzy more than I usually could, and take rests.
Now, the benefits last for an entire day.