I doubt many people have tested kashima and non kashima side by side on the same bike with stanchions covered to avoid prejudice.
I have too.
I don’t like Kashima on a shock, as it feels like it needs more damping and it moves too much. I like some stichion in my shock, rather than more damping.
I also didn’t notice much difference at all performance wise between a well serviced RS SID RLT Ti, and a Fox RLC FiT Kashima.
I’m pretty sensitive to change, pressures etc too. To the point when I noticed that I had about 2ml too much oil in my lowers.
I think the real benefit is durability, my Fox Kashima stanchions had no wear after 8 months of good use, in all weather. My SIDs, and my other Fox showed wear over the same period.
Similar service intervals, well… the Fox had less care than the SIDs really.
The SKF seals did make a difference though, like Loco says.