I settled on Yellows in the front and Reds in the rear for my front-motor XV-01. The reason I use Yellows in the front instead of Blues is because I'm running much thicker oil in the front, so the front suspension can be more compliant for better traction in corners, while still resisting bottoming-out on sharp impacts like running over the edge of a sidewalk slab that's sticking up a little

On my long-damper rally builds, I use the TRF201 front-shock tuning springs, with Blues in the front and Reds in the rear.