I have both picked up at Harbor Fright and ordered on amazon; both same quality for me and never broke down like that.
https://www.harborfreight.com/25-lbs-coarse-grade-walnut-shell-blast-media-92150.html
https://www.amazon.com/gp/product/B0063GTFXS/ref=ppx_yo_dt_b_search_asin_title

Didn’t know it came as a cat litter. I buy crushed walnut shells used for reptile bedding. Works great. I also add an ounce of this.

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Here's what I use. Will not break down and very little dust, if any at all.

I bought some cheap stuff off Amazon a few years ago and it was a nightmare. It was too fine and kept clumping up in corners of parts and the dust it created was ridiculous. I ended up throwing most of it away.

And it doesn't matter what media you use, your parts are going to touch.

https://www.chewy.com/kaytee-walnut-natural-bird-litter/dp/122945?utm_source=google-product&utm_medium=cpc&utm_campaign=12791145766&utm_content=Kaytee&utm_term=&gclid=CjwKCAjw682TBhATEiwA9crl3ziIwnfU4CGg6e9hTYt5Lnfgtm4frDWV_bbIvzSspQ4KhVmYJE8FYRoCvdYQAvD_BwE

Pick one and go with it I personally use Mother Mag polish and think it does a much better job than Fitz but tons of people use that and love it.

I like the White Diamond. Smells like vanilla and drastically cuts down on polishing time.

Agreed. Not sure if it matters what you use but you definitely need a liquid additive.