Supreme unleaded in an old MFI engine. Any difference?
I've read a few conflicting articles on a few different sites and videos on YouTube and was wondering what you guys think?

From what I can gather most people say higher octane unleaded fuel makes older engines running a carb or mechanical fuel injection set up (like my mk4 xr3i), run miles smoother and can eliminate some running issues, but also that it has little effect on newer engines with more sensors etc.

Thoughts??