My experience matches Keith's. I tried 5-3-1 immediately after a novice progression and basically wasted a lot of time. I had fun, and learned some things about programming.
But I'd have been a lot better off asking a coach for help with transitioning from novice to a weekly program.
For one thing, the coach would have immediately recognized that I really just needed to fix my squat form, eat more, get my T tested, and continue novice progression.
If you look at the advanced-intermediate and advanced programs in PPST, many look a lot like 5-3-1 variants.
But the book recommends using a weekly program for as long as possible before going to programming that increases weights every 4 weeks.