I will confirm that Vile is an excellent editor. I don't know if I'd consider it a vi-clone, because the vi-ness is kind of skin-deep, but it's performant and works well.

(In school, early 90's, there was a large vile following on VMS, which is where I mostly used it. I don't recall why it was preferred to Vim on VMS, however. Perhaps we didn't have Vim easily available or installed. But I digress.)