B4 rear hubs

[xavi]

I would like to know, what rear hubs do you use? And what's the difference with old ones (B4 standard), its effects and results.

B4 standard
B44
Rayspeed 0 - 0.5 degrees
Yokomo 0.5 - 1 (Is it too much?) degrees (Does Yokomo rear hubs fits on B4?)
Racer's Edge 0 - 0.5 - 1
Trinity 0 - 0.5

What rear hubs was used by Hayato at Worlds? It seems Rayspeed, but the color ... (D4?)

Sorry for my English