I dropped out of a PGCE when I did it because of the work.
In all honesty it wasn't a good time for me because I'd had glandular fever the previous year badly and was still struggling with my health, so I probably should have taken a year off.
For some reason our subject they treated us totally differently from the other subject PGCEs (secondary maths). Things like all half term/bank holidays etc we were expected to come into the uni. Occasional weekend days were added and evenings. Even when everyone was in college we had no breaks at the same time as other subjects which was fairly miserable in a lot of ways and our breaks were shorter and we did about 90 minutes longer at the end of the day.
Once we were in school full time, we had essays and projects to do on top of this and then half term we were in the uni 9am-5pm each day, when the other subjects were told to use the week doing lesson plans and the assignments set for the week.
We were given dire warnings about missing a day meant they would mark us down for "not being professional".
My school had no text books, just filing cabinets in goodness knows what order, neither of us students could work it out, and the teachers tended to be very vague. You'd ask for "multiplying out formula" and they'd say "look under algebra" where there would be about 1500 different worksheets and working through those took time!
So we were normally not just preparing the lesson plan, but also designing worksheets on top a lot of the time. We shared when we could but had very different groups.
The point came when I woke up with serious stomach cramps (having been told that was a symptom after GF to watch out for) during the half term and staggered into college. I phoned the doctor (from pay phone) and begged for an appointment in the evening. They said they couldn't do that, but if I phoned at 10:55, which was 5 minutes before our morning break, they'd get the doctor to talk to me.
The subject leader, when I requested to go 5 minutes early - bearing in mind I was clearly quite ill at that point, refused to let me go as "a teacher can't decide to go 5 minutes before the break".
Then the leader announced to the class with no trace of irony that they had a doctors appointment they couldn't get out of, so we had a 2 hour lunch.
So I got down to the doctors in that 2 hours, and the doctor told me that I needed to stop. He also said I was the third student from my subject specialism that was dropping out that year - the other two entirely due to stress, and there had been 5 the previous year, all due to stress.
So I stopped, and the relief I felt was amazing.
I suspect I could have been a reasonable teacher. I've get good rapport with that age, I know my subject and I can explain reasonably well. And I could have coped with the hours the other subjects had - just not the relentless never stopping one we had. Never wanted to go back. If the aim of the course was to put people off teaching then it was excellent.