I can't even fathom spending $10-25 on bulk load Leica-brand cassettes. I do have one of the Nikon ones that are similar and I literally could not even figure it out and I decided I didn't feel like reading a freakin' manual for a bulk load cassette! I'm a man after all.
The Kalt cassettes are just fine. There's occasionally one that has weak light-trap felt and it falls off after using it a few times. Big deal. Toss it. I've only had a couple like that, and then the other ones last much longer (they also last better if you don't leave the leader out and open up the cassettes in the dark for loading into the developing tank, rather than leader out and pulling the film out of the cassette backwards. That's where all the problems I've had originated). I like the screw caps, I've heard too many horror stories from the snap-ons, which inherently will fail with a pressure fit mechanism.
I have like 50 cassettes (which would cost $1,000 for IXMOOs! Come on, really?) and I have a few different films/bulk loaders that I like to switch out and fill up cassettes. A tip - I use the bulk load cans to hold 10 or so rolls at a time, for organizing them (different films).
I was scared to bulk load for a long time but in reality it's simple and effective. I haven't had any issues with dust. I use a strip of simple scotch tape to hold the film to the reel, usually just long enough to tape both sides of the film to it. No issues with tearing it out in the camera, even using it in high-powered modern cameras like my F4 and F5.