The oven self-clean function, in theory, is a great idea, but on most models it puts a tremendous strain on the heating elements, and on the appliance as a whole. It is even possible for a small safety fuse at the back of the oven to burn out, completely disabling the bake function because of the high temperatures involved.
Now, replacing this fuse is not difficult, but it does involve pulling the oven out in order to be able to access the back panel. Kind of a pain in the bee-hive. If you are still set on doing a self-clean, I recommend you wait until AFTER that important dinner or event, just to avoid potential problems. Gotta make that Turkey!
So due to the design problems of many of these modern stoves, the self-clean option should be used sparingly.