I used RTM for a year, but found data entry to labor intensive.
I hate having to add a task, hit enter, scroll through my list select the task, check Edit, then add tags, dates, notes etc. Way too much work to capture the task. I know there are some shortcuts ^, ! etc. But, I found that if it is that much work to enter a task, I was not entering tasks.
I'm using Google Tasks and the GTasks app now. I'm very simple in my lists. Task name, support note (maybe) and due date(maybe). Sure, I'd like tagging and location options, but I can live without them in favor of the simplicity.