If you take the full 90 second rests you have over 30 minutes just resting. I did the workout last night in 90 minutes

**** near 2 hours if the gym is packed

The first few days you're getting used to the high rep volume, so it might take up to 2 hours. I'm at day 4 now and my body already fully adapted to it. It takes me 1h 15min to complete the workout and i do 12 reps on all sets. I'll probably be able to do it in 1 hour, starting next week. Just focus, don't f*ck around and put in WORK!