While I think that much more of ski performance can be objectively measured than is currently done, it is certainly true that there are so many variables when marrying a skier to a ski that it is very difficult to predict how that skier will respond. Also, as adaptable beings, we tend to find ourselves adjusting rather than complaining.
I, personally, prefer the system bindings in most cases due to the way that they skis arc and also for ease of maintenance and adjustment (there's something to be said for being able to mount your skis in your living room!). But, feel can trump this. For example, I never liked the Volkl g3 in the Motion, but loved it in the flat version.