When I was first keeping snakes I kept some together, I never had any deaths but feeding was a hassle, I'd usually have to feed them both at the same time and supervise to make sure nothing went wrong, and if one snake finished first and was looking for more I'd quickly have to feed it again so the other could finish, etc etc. Unless it was for a display cage(I may keep a group of Chondros in a large vivarium with live plants etc) or something unusual I wouldn't bother doing it again with pythons or most other species. Not so much for the risk of one eating another, just to save myself the hassle.