I just received the Deda Elementi Zero 100 stem (size: 100 mm) I ordered last week. Just for curiosity I weighed it. It is only 125 g with CrMo steel screws!

I am so glad I returned the Zipp Service Course SL stem.

Zipp Service Course SL Stem & Quadlock Handlebar/Stem Mount - Bike Forums

100mm Service Course SL stem is 134g, don't think those 9 grams were holding you back too much, but glad you like your new stem.

The switch was not for weight reduction, but because the Zipp stem is so wide that it would have displaced the Quadlock mount for my iPhone. That phone alone is 228 g so you are right that the 9 g makes no difference.

So the Zipp is lighter as it saves you the weight of the phone and mount

I had a 110mm Kalloy Uno that looked pretty nice, was around 120g. But together with the Toseek Aeronova copy, also quite light at 230g, my front end soaked up half the power when I stood on it.

Swapped out the Kalloy for a beefy Zipp number, I think it weighs 160g or so, and problem solved. Now the flex in the bars worked more like a spring to store and return most of the energy it absorbed. After that experience, I'm not interested saving weight on the stern - it's doing too much to skimp on material.

120g for a 100mm stem seems pretty ordinary.

And I don't understand how any particular stem prevents you from mounting a quad lock or any other type of mount.

Not a purist like so many of my fellow Bike Forums \ Road Cycling members; I must have my phone.

125 g is not ground breaking, but certainly below average for a 100 mm aluminum alloy stem.

The center portion of my handlebars is not wide enough for both the extra wide clamp of the Zipp Service Course stem and the band clamp of the Quad Lock Out Front Pro mount.

Of course, the Cannondale C3 stem that came with the bike is only 113 g.

This is the part where I tell you how the Deda stem is so much stiffer and allows me to really put down the power, especially out of the saddle. But in reality the only discernible difference is the slightly lower position