what do you mean when you say "newer"?
bins continue to get better, as can be seen by comparing an "average" luxeon today and an "averagea" luxeon from several months ago /ubbthreads/images/graemlins/grin.gif
"best" really depends. there is no way to call one led the "best". it all depends on application.
even within the individual wattages different bins can be better for certain applications.
generally speaking the highest lumen rating with the lowest vf is ideal, but sometimes you want a higher vf if you're going to overdrive considerably, or sometimes you want a purpleish luxeon for something, or whatever... /ubbthreads/images/graemlins/icon3.gif