Both are very good editors. The choice might well depend on which source language you're going to edit, and your average file as well as project size (how many files?). If any of the two is large enough, you just can't use Atom for that - it's noticeably slower, for obvious reasons. Though, I don't use a single editor for everything. You could just go with Sublime, and switch to Atom whenever you need some feature/plugin that you find more convenient there.

OT: does anybody know PSPad? It has a very interesting feature set, though it lacks more advanced things like collapsing, refactoring tools; I find it very useful sometimes - especially its columnar editing feature.