What I noticed was the diffusion is top notch. I compared it to a stock Vader ESB and a stock Maul and the diffusion is the best so far.
The ESB Vader I compared it with (side by side) was just as evenly lit.
Keep in mind blade uniformity can vary from saber to saber IN THE SAME MODEL as a result of "luck of the draw" manufacturing. Others have confirmed that not all MR sabers are exctly the same, and since the LEDs are glued in place by hand, somtimes it turns out better than others.
Also, if you play with your MR (i.e. duelling, practicing spins and inevitably dropping it now and then), even if the LEDs remain intact, they do get jostled around and I have seen perfectly even blades become slightly less even. Thus, comparing ANY used blade with a new one will most likely make the new one seem perfect.
It's probably not a cooincidence that my freind's ESB I used for the comparison just sits on display. He never touches it.