Somewhat less risky than coffee after dinner. It’s not a physical stimulant, only cognitive. In fact it’s this lack of physical stimulation that those looking for an adderall or even caffeine substitute most often complain about. Sometimes they don’t think it’s doing anything, because they’re looking for the wrong effects.
Personally I’ve never had an issue sleeping with Moda or Armoda. I could take a nap at the height of its effects. The only impact from it that might disrupt me is that some train of thought is so interesting I put off sleep. However, if you take Modafinil by 10AM it’s highly unlikely to still have an effect by bedtime (if anything it’s too short acting). Armodafinil (a “purer” form containing only the R isomer, instead of 50/50 mix with S, the faster onset shorter acting isomer Modafinil contains). Armoda lasts longer and should be taken earlier. Also, your body will ramp up production of the enzyme that breaks Modafinil down, peaking after the first month, so duration and intensity drops off quickly, and by 30 days or so it levels off and you can maintain a stable dose for the same effect from then on.
Absolutely killer stuff for long drives or quickly ramping up in a new time zone.
I read somewhere the State Department supplies 50,000+ a year to traveling diplomatic staff, Presidents from Obama on used it while traveling, and the US military replaced amphetamine “go pills” for pilots and special operators with Modafinil getting better results with far fewer side effects and no stimulant crash.