I don't know about magnesium citrate, Invincible said the citrates
does not relax only the sulfate. As soon as Andreas forum is open I am planning to ask him. He mentions in his book you can replace the citrate for the sulfate.
I think the person that started this thread said the flush was as succesful with the citrate as the sulfate and I have no doubt, I meant with being succesful it is the contraction of the gallbladder with the OO/GFJ that terminates how many stones you get. The magnesium makes it easier for the stones to come out. Some flushes like Julia Chang's don't even use magnesium and still are succesful.
I just checked back and it is you that mentioned that. So I agree that it can be good because the contraction of the gallbladder is dictated by the OO/GFJ.
But it is not good or bad because of the citrate or sulfate, some people do a salt water flush in the morning and still do well.