i must disagree. The trilogy is quite hard, J5 isn't a easy cut, i can do it in 2 weeks of practice, i'm just not extremely fast and smooth. It all depends on skill level. Lethal is terrible teaching. System isn't too bad, but if i were you if your say 1-3 months. Trilogy 3-5 System 5-7 Lethal
i'm only 5...and a mistake i have them all lol. But i can do all of the cuts so it doesn't matter.