If everything fits and is comfortable, you don't need to change anything.

Sometimes we need to change things. I'm in that process. I'm not definitely clear on how much rise and reach I need. It's much easier to make experimental changes with a modern stem, especially because the removable faceplate allows quick removal and replacement of the handlebar. As others point out, there is a wide variety of products available.

On the topic of the Innicyle (rather than a debate between threaded and threadless stems), I have had one for several years, and it's lived on a couple of bikes, most recently on the bike I rode in this year's Cino in Montana. A problem I've had is that I sometimes can't quite tighten the wedge within the steerer tube enough to prevent the unit from rotating while riding. For Cino, I tried applying some Park Tool SuperGrip to the inside of the steerer, and that worked for awhile, including rides up to Cino and through most of day 1, but by the end of day 1 and at the start of day 2, my bars were flopping around such that I thought I'd have to DNF. Instead, I tried loosening the wedge bolt and then tightening the beejeezus out of it, and it held for the rest of the ride. In fact, getting the Innicyle unit out of the steerer tube once I was back home required lots of effort. I've seen some similar complaints with the early generation Innicyle on this forum, so I'm guessing they somehow addressed the problem in later iterations.

From the video it appears a nice quality piece, perhaps it only cleans up the aesthetic of the headset upper bearing. Yet I've no experience with the system, I question it especially for the high price.

If one needs the threadless stem with all its advantages as mentioned, the simple threadless adapter for under $10 does the same. Plus you can raise and lower the height as the traditional quill stem.

This brings us to the term quill. The inni system really is a quill type and the video host even calls it such. But, once you set the bearing preload, its done. Now one still has to play with spacers to adjust bar height. Few like to keep the excess pipe protrusion, so its usually cut. Now you're left with a shorter vertical section and might not be as useful for another bike or if you later change your mind and wish to raise it.

Bearings. Would like to know more about them and of replacement. Tapered vs ball, type, end thrust preload is a study in itself. Definitely a critical part. Can completely change the handling and control of the bike.

Lastly, the argumentment one saves a few grams is moot.

Maybe the later model has a Japanese style wedge (angled edge) rather than the Italian style. That seems more reliable.

there are an increasing number of 35mm Bars around too.. and MTB flat bars, one piece CF Cockpits, etc.
This adapter is a fantastic option to have available, that opens up a number of other options, IMO.

i have swapped drop bars, slipped on and located the new brifters to taste, cabled everything, taped up the bars, and carefully slammed the plugs in....... then, on the first ride, the customer decided she wanted the original bars back on the bike, but didn't think she should pay for anything, since, after all, it Was her original bars............
The bike had a one bolt System One Trek stem on it.. i used 3M gorilla snot glue under the bar tape, the second time around.

I finally got her onto a real road bike two years later... she does short-ish triathlons a couple times a year... her previous bike was a 930 Trek MTB with skinny tires.. it is now her "spare bike"

The one shown in the video is a quill type with cone wedge.
I don't understand the advantage of the Innicycle solution over a standard threaded-to-threadless adapter; is there one?
Also, people keep mentioning that there's a weight reduction, but I don't see that either. 1-1/8 inch stems seem pretty partsy and clunky to me, so how are they lighter? Thinner walls to go along with the thicker cross-section?

The two Serotta Nova Special

Standard Profile Design threadless adapter with titanium wedge bolt and aluminum wedge. Ti bolts in stem
https://www.bikeforums.net/classic-vintage/1069707-what-have-you-been-wrenching-lately-350.html#post23400107 #8736


Long 1" steerer with internal threadless plug, titanium stem/bolts, and 1" threadless headset
https://www.bikeforums.net/classic-vintage/1299051-show-us-your-lighest-vintage-steel-bike.html#post23327321 #4

Your aesthetic preferences aside, the fact remains that there is currently a vastly wider selection of 31.8 handlebars. Threadless stems are also widely available and most are much cheaper than the Nitto UI, which is particularly helpful for dialing in fit.