I bought it as soon as it came out, but I couldn't listen to it except for a part, and today I listened to the remaining part while looking through the PDF!! It was a purchase without regrets!! I still remember listening to Younghan's roadmap around April or May last year... It's really the best lecture, a lecture you can trust! If you're thinking about it, buy it right away! I listened to it well ㅎㅎ