I've been using bulletjournal since January 1st this year and it's been working wonderfully. Prior to it I used GTD with Things and Wunderlist, but they always ended falling apart.
Why did Things and Wunderlist fall apart? (Could it be that you did not schedule and do the weekly review? I've had that problem myself.)
Wunderlist had serious sync problems that made it impossible to trust.
I don't know if they solved the problem though.
I've been taking notes inspired by this for two months now and like it a lot. I make calendar month pages with a one-line note of what I did each day, and seeing these build up is quite satisfying.