I think its more about how much power you can apply through the component. Years ago when I was mtn biking a lot I was putting in the top-o-the-line bottom brackets, and I kept breaking them. When I dropped down a level or two they used heavier, and stronger parts, so I stopped breaking them.
these days that may no longer be true, and some components like a derailleur should not see a force load anyway, so for those it shouldn't matter.
Last edited by Haff; 06-15-15 at 02:54 PM.
Reason: bad grammah