I use the convection setting most of the time. The savings in time is most pronounced if the cooking time is long. I've noticed very little difference with cookies and cakes. I usually check about 5-10 minutes early. The more you use it, the more familiar you will be with when to start checking.
Last thanksgiving we cooked a turkey in one at my brothers. It was great!! cooked all the way through but the bird remained nice an juicy with a great golden skin. It took much less time to cook than with a conventional oven.