I have only heard of one case personally and it was likely due to install error. The stud in this instance was torqued to the manifold to the spec the nut was supposed to be and basically doubled the force applied to the stud. I have also been a little suspicious of guys like czp selling Ramey studs with gold zinc plating that the originals don't come in. The story I hear is they purchase them and then go to the trouble of plating them before reselling. It seems a little fishy to me especially in the light of all of the parts counterfeiting going on. Make sure to purchase from a reputable seller.
