The Protestants I have read seem to consider “Paulism” as a form of proto-Protestantism. I have not heard that they embraced Nestorism before.
The Nestorianism starts right around this post (it’s not a real long thread):
http://www.freerepublic.com/focus/religion/2316615/posts?page=46#27
“I have not heard that they embraced Nestorism before.”
Around here Nestorianism and Iconoclasm are the commonest, most often found heresies. Thy both pop up with truly alarming frequency among protestant posters.