Can be good if you're what they want
The job was good. It was varied and had very good depth. There were obvious avenues for progression also (if you were the right candidate).
The people were nice enough, but talked a lot. There were a lot of expectations because of this.
Given production targets were important, work done was metered: some people would still work more, take everyone's work; causing many others to have lower numbers.
Management were reasonable, though you are expendable and they will move you around as they see fit – in particular if you don't fit in.
If you don't fit in in fact, they will likely get rid of you. What adds to that is there is plenty of room for error in doing the role, given concentration for 12 hours is the norm; as well as a multitude of other factors in the other roles.
It seems if favour is not given to you as the worker, after your work , they will not consider, or at least heavily weigh against giving you work – the agency are fickle.
Good work, good pay, some progression opportunities
Hidden expectations - If your face doesn't fit... Haughtiness can make life very hard