I have 3 levels of sort: Date, Priority and Custom Field. Date seems to sort okay, except that tasks become "overdue" at 4am in my timezone so all day anything without a time set is "overdue". But Priorities and Custom Field are inconsistent. I have a task, today, that has a "Normal" priority that is ahead of all the tasks with "Urgent" or "High" priority. Other times it is off in other ways.