How effective is Modalert 200 for studying?

https://www.smartfinil.net/product/modalert-200/

Modalert 200 improves cognition and attention, making it desirable for studying. Users experience increased alertness, attention, and motivation, which may help academically. Some may notice considerable productivity and knowledge retention gains, while others may not. Modafinil helps sustain alertness and attention, not intellect or knowledge.