Just thought I’d throw my 2 cents in.
Within about 10 weeks ago I started a 6 week cycle of 5/3/1.
It looked like this.
Monday- Lower Body- Squats 5/3/1 (maybe accessory work depending on how fried lower back was)
Thursday- Upper Body- Bench 5/3/1, rows delts upperback etc
I did it for 6 weeks, 5/3/1 then added 5kg to each of the working weights 5/3/1. (no deload week as per book being in gym only 2x per week)
Before I started my ALL TIME best squat was 210kg, but my max at the time was probably closer to 200kg. Therefore all working sets were based on 180kg.
After 6 weeks I hit my 1 rep on squat, then went on to work up to a max. I hit an easy 227.5kg (500lbs). So the book well worth the $25.
The only con. I was wearing a lever belt and it was a bit tight. When you get 10 reps with a weight you should be hitting 1-3 times and are wearing a tight belt, it is very uncomfortable. The next time I run 5/3/1, no belt.