Maybe it's just my 4gigs of RAM speaking, but Cursive is sluggish and heavy. I have Emacs running in a drop down terminal, that I can hide and show fast, I can run many languages simultaneously (Python and Clojure for me), I can quickly navigate and to all sorts of things without any load time. Everything feels very effortless, thus why I'd recommend Emacs. Not to say that I am above opening up Cursive for serious refactoring or navigation. :)

NB: I personally also hate using the mouse.