I love Bully breeds myself and would love a Boeboel but that is a serious, better have your crap together dog! Someone on here has one but I can't remember who?
Not a fan of Shar Pei or Chows myself, think they are both pretty much the same.
Newfies are pretty much gentle giants. Leonberger don't know but in general the Newfies was breed to "save" people the others you listed..not so much!