That’s good to know Garrett. I think I ran into this exact issue with my first kendamas and didn’t realize why. My first was a Sweets marble finish and yeah, it was pretty slippy. But since I had nothing to compare it with I didn’t know. Then I bought a KendamaUSA pro model with a paduak ken and that mint green satin finish tama and it make a HUGE difference immediately.
The marble is still a nice kendama, it just took a while to break it in.
I just had a realization: When you ding a yoyo you think “Oh No! Not another ding!” When you ding a kendama you think “Cool, now it will grip even better.”