Over the past few semesters of using OnDemand we have decided that using it for essay questions has certain issues and has accessibility restraints for students.
The OnDemand word processor has no formatting options, cut and paste is not available and students with accessibility needs are not catered for.
Word has a more robust workflow, from opening the app, to back ups during the exam to final delivery of the work. It is a tried and tested work flow that we have honed over several years.