The smaller ones are my Trent's absolute favorite toy in the world!
Here's the stash we found of them
Anyway, I haven't had any problems with these, but they aren't exactly the same as the ones you posted. I have gotten those bigger ones with the long strands, but my two weren't really interested (I don't think they roll as well as the smaller ones). I don't buy the ones marketed for cats, I buy the bags in the craft department that are, I think, 12 balls for $2. I get the ones that are at least 1" diameter, not the multi-pack with various sizes.