I think you're probably right about the unbeatable gloss and depth of S100 but after using it since 1998 until about a year ago I can tell you I've pretty much quit on it. The cleaner/pretreatment is really nice stuff but after I use that to get the paint ready for a wax I just don't follow it up with S100 wax any longer. If you don't daily drive the vehicle and its garaged then S100 is some impressive wax. If your vehicle is going to see sun and rain then you'll be doing a monthly S100. Where as a paint cleanup with S100 and AIO gets a good couple months of slick paint. I'm not a detailer but I do like to wax my vehicles from time to time.
Well like I said, I re-apply it every week -- at least in the summer. I don't mind because it takes no time at all to do it. That being said, I make sure to always have a base of opti-seal to give me good UV protection.