Both vim and emacs can split (either horizontally or vertically) to show as many files as your typeface can usefully cram in. As a greybeard, I learned the vim predecessor vi, which didn't have that ability, then learned emacs, which at the time (1984) did, so my calcified reflexes use vi first (because there aren't any more Unix boxes that don't have it) but switch to emacs as soon as I'm going to want more than one file on the screen - since (in my environments) emacs is everywhere that vim is, and I haven't taken the time to learn the Vim way to do things. In my opinion, emacs and vim are both superb editors, but both need time spent to get reflexes into your fingers to operate - i.e., they're both "expert friendly", and perhaps "casual hostile".