Pros
I would definitely say that the hours are flexible here at the Graide Network. Just as other freelance jobs, you pick up work as you have time to do so and grade when you can. As far as I can tell there aren't any penalties for not working a certain amount of hours. Additionally, at peak times of the year (during the fall and spring semesters) there is an abundant amount of work that you can pick up if you want to work.
Cons
It seems that the pay scale is very low, especially for how much work graiders put into grading these assignments. You are paid on an hourly basis, based on the allotted time of hours that the network gives you in order to complete the assignment. If you go over the amount of hours allotted to an assignment, you will not be paid for the extra time that you took grading the assignment. However, there are instances in which in the assignment sections, there are students who did not do their work, so you will skip these students. If you skip a large amount of students (who didn't do the assignment) you will not get paid for the full time even if it took you that long.