I've tested a couple of the mentioned drugs myself and thought i'd chip in with my results and learnings
Modafinil/Armodafinil
Definitely works and the side effects are neglectable. It's much as he describes it but im not sure why he can't feel it some of the time as the effect on me is really strong, especially with armodafinil which was almost too much to be hanging around other people :) You feel very awake like a mild cocaine high but have an easy time focusing on the task you are doing, i can definitely recommend it for all nighters and situations where you have to get something out the door !
Melatonin
I've experienced quite a bit with this, since i have really really hard time falling asleep. It's actually a huge issue for me. i've found that "microdosing" works even better than taking the "normal dose" of 2-3mg. I found a supplier in the Netherlands who sells 300ug pills and they have worked wonders for me ! works just as well as the stronger dose but it seems that the lower dose makes you sleep better.
Just my 2 cents :)