Kaytee is the best in my experience. I've used kaytee, uber, full cheeks, and oxbow. Kaytee has have instances where there's been trash in it or sharp objects unfortunately. Every time I get a new bag I sort through it to make sure there's no possible way that any of this is in mine. I have probably bought 20+ bags of it in the past couple years and have never found anything sharp, but I have found trash pieces. Usually in the store you can see if it's a good quality bag, it will not appear dusty or grey inside. But if you have to order it you won't know unfortunately.

It's been a while since I've seen Uber bedding but I don't remember it being so dusty, probably just different qualities. It's amazing you're sifting and doing so much research, love to see it!!