There was a thread that just got pruned about recursion. I didn't get the chance to post in it and the thread had the unanimous opinion that recursion is always slower than iterative loops. THIS IS NOT TRUE.

Some compilers have recursive function call optimisations and will turn your recursive calls into loops. If the language you're using is designed with recursion in mind such as Lisp you can be sure that recursive function calls have the same performance as loops. The compiler will stack each call iteratively or use tail call optimisation -- same performance as loops. A word of warning, though this does not apply to most languages.