Well, it's a true full "undo" behavior. It's a bit annoying at times because edits are not grouped, but you can see your entire editing history when you're undo

Well, it's a true full "undo" behavior. It's a bit annoying at times because edits are not grouped, but you can see your entire editing history when you're undoing: no edit is ever lost in this manner. As typical in emacs, this is not the only undo behavior you can have. undo-tree behaves very similarly to vim by default, but still preserves the entire editing history (with branching), which is visible graphically with "C-x u".