I used to use the 3-step deal religiously. Pre-wax cleaner once every few months, then glaze and wax every week. It's not hard to apply like some waxes and it's fairly cheap. The shine you get if you do it right is also very nice, though it goes away quickly.
If all you want is a quick one-wax-and-done every 3 months, I'd say 3M cleaner wax... or if you're even more merciless on your paint and you bring it through the automatic car wash, a few coats of Liquid Glass. Of course you won't be getting the best shine, but if it looks good to you, who cares?