I've been using Modafinil daily for about 2,5 years and I am currently under its effect. I buy it online and pay with Bitcoins. I use armodafinil if I want more focus, and I use modafinil if I am tired. I don't take the full dose, which is 150mg (armodafinil) /200mg (modafinil)- I break the tablets into 4 and pop them if I feel like I am unfocused or tired. In the course of the day, I rarely take more than 1 full dose. For reference, I know of people who take it for narcolepsy who routinely consume 8 full doses a day (200mg x 8). For me it's been a clear net benefit without any noticeable side effects. I think it makes me about 20% "smarter"/"better", let's me learn and achieve more and generally improves my life.