How do you define success?
I'm a RNY to DS revision myself. I consider the decision to be one of the best decisions I've ever made. I feel like a success...which is good enough for me. Quite a few of us out there are RNY to DS revisions.
However this is a major life change and it requires diligence for life. Supplementation, lab work, the balls to be your own patient advocate in the face of the medical community who might not have experience dealing with a DSer. It's all super important, but it's very worth it if you make that commitment to yourself. Like Munchkin said, it requires a revision surgeon because this is the most hardcore of revision surgeries. There are only a handful doing it, so you might have to travel depending on where you live.