Instead of mapping to Escape (or Control) I prefer mapping Caps Lock to ISO Level3 Shift, also known as AltGr. That way I get a whole new type of modifier that I can use to assign custom functionality to.

For example I map AltGr+j/k/l/i to the arrow keys so that I can navigate code without taking my fingers of the home row, regardless of the editor I am in. I also have AltGr+h mapped to Backspace, AltGr+m is delete, AltGr+u/o are home/end and so on and so forth. It opens up lots of possibilties.