The sticking point for me is that if I discover some functionality is missing, I can add it to Emacs on the fly with often just a few (1--25) lines of Lisp.
So there's several tiers to this convenience:
1. Does it do the obviously important things out of the box, or with easily installed add-ons? For most editors, this is yes.
2. Does it do the little things out of the box, or with easily installed add-ons? For some editors, this is yes.
3. If none of the above, can you create the thing you need as an add-on without breaking your step, almost as part of what you were already doing? To get to this point it takes a very dynamic system like Emacs.
So there's several tiers to this convenience:
1. Does it do the obviously important things out of the box, or with easily installed add-ons? For most editors, this is yes.
2. Does it do the little things out of the box, or with easily installed add-ons? For some editors, this is yes.
3. If none of the above, can you create the thing you need as an add-on without breaking your step, almost as part of what you were already doing? To get to this point it takes a very dynamic system like Emacs.