Replacement Nova Cole Jaw grips/buffers

Not really happy with my Nova Cole Jaws right now. To me, the standard set of the grey rubber bumpers that come with the jaws don't grip very well. Does anyone have any experience with the "upgraded" bumpers that come here [https://www.woodcraft.com/products/nova-6030-cole-jaw-buffer-accessory](https://www.woodcraft.com/products/nova-6030-cole-jaw-buffer-accessory)

Or does anyone have experience with these grips?

[https://www.etsy.com/listing/196646126/special-tall-grippers-for-nova?ref=shop\_home\_active\_2&crt=1](https://www.etsy.com/listing/196646126/special-tall-grippers-for-nova?ref=shop_home_active_2&crt=1)

I'd love to get a vacuum chuck, but I don't know if it fits my Harbor Freight 12/33.

Any other recommendations?