I have used all the major GTD solutions from OF, Things Todoist, 2Do, etc. This update of RTM is by far the best one for my needs and hits on all the features necessary for a good productivity system: multi platform, subtasks, start dates, awesome filtering, emailing tasks, multiple tags, and simple to use.
One recommendation for a future update would be the ability to create a task in the inbox and designate that it should be a subtask of an already created task. Also reminders can only be set up for task with start or end dates (Id like to remind myself of Someday tasks which have neither).
Overall this is a great app and worth your consideration- especially if you need cross platform functionality. Great customer service also! Thanks
DW_021616 about Remember The Milk: To-Do List, v4.0.41