Russian magic chalk (RMC). I got on the Kamui bandwaggon when they first introduced it. It was good, but it ruined cue balls. I tried several chalks, but never found one I liked like Kamui. I tried RMC and liked it. It has enough grit that you can kind of work your tip if it gets a bit shiny. I tried Taom Pyro. I like it. Kind of similar to Kamui, but no mess and lasts long. Something wasn't right. I missed the "gritty" feel when applying chalk. Went back to RMC and I like it much better. Playing some local tournaments, they had Masters sitting on the table so I used it. Decent feel, decent grit. I'm kind of deciding if I take the Master pill or keep with the RMC. I have some pre-flag masters at home, it's decent, but the new stuff is ok too. Honestly I'm to the point that it doesn't matter. As long as it's not Sportscraft, I'll use it. Chalk doesn't cause miscues, bad strokes do. I enjoy a chalk that takes some thought, same as checking a rack for tightness, any little nit picky things to do can get you in the zone.
I recently tried Kamui again and I'm no longer a fan. It's great chalk but I like the grit. I know they make a grittier one now, but if I'm paying $25 for a cube, I'd rather just pay $5 or $0.50 for a cube.
One thing I found is this post:
https://forums.azbilliards.com/threads/layered-tips-glazing-over.189715/post-2452902 . I had one of these strange tip tools, not really a pick, not really a scuffer. It came in the case when buying a used cue. This simple trick makes ANY chalk perform better. I use a hard Ki-Tech tip and it holds chalk well, but with this trick, it holds chalk like a fluffy Elkmaster.