It's recommended to have a small spacer above the stem with a full carbon fork. 3 spacers of 1mm isn't much in my opinion. Plus the spacers i put are cool with the cut-outs.
Finally negative stems are just sexier, more race oriented. Like the Cinelli MASH stem that can only be put on the negative to -17'
10mm I assume you mean.
But why would you have the frame made the wrong size in the first place?
30mm of spacers is fine but when you have the option to have a bike made to your exact size, why would you have any?
It's recommended to have a small spacer above the stem with a full carbon fork. 3 spacers of 1mm isn't much in my opinion. Plus the spacers i put are cool with the cut-outs.
Finally negative stems are just sexier, more race oriented. Like the Cinelli MASH stem that can only be put on the negative to -17'