I did not pass the first time (missed it by 6 questions), though I didn't use TDC. I used Gerry Grossman's L&E book and felt extremely lost with it. I went into this exam feeling very confident, though the last part was tricky and somewhat unfamiliar. Still, 5x more confident than the first time taking it. Thank you so much. Worth every penny. Looking forward to using TDC for my clinical exam in the near future.