Well... define best.
E.g. I find Atlas Code 100 easiest to work with, and easiest to have trains run on reliably and smoothly. Mind you, I don't use it on my layout because it looks toy-like and out of scale. But on the 'easy to work with' front, it wins for me. So best somewhat depends on what you're seeking most.
If, as I suspect, you've got code 70 as a given, then you're basically down to deciding between shinohara and microengineering: I definitely vote shinohara. I find it near impossible to get nice even curves out of ME despite watching numerous tutorials, etc. and for my fat fingers, at least, I find it awfully fragile.