Dad, I have been on it over a year and am grateful for it. The fatigue has been so much better. It used to be debilitating. The flair-ups in general don't come as often and when they do, they are much shorter in duration. In the beginning I had some weird side effects like an upset stomach, etc but they went away pretty quickly. I've had no other issues since. I'm one of the ones that would swear by it.
As a side note, it was initially used for malaria for our troops. The fact that guys with RA were getting better was secondary. It is used very commonly for lupus and can be a crucial med for them. One of the things that eased my mind about this med was that it has such a long history of use.