Instruct: Classify a review into positive or negative sentiment.
Query: They don't last and are so-so in function

In their advertising, the distributor claims that these balls last for years. One of mine broke into pieces after a few months of light use. Don't waste your money. I'm especially disappointed because my son is very sensitive to any fabric softeners so I cannot use them or any sort of dryer sheet. The manufacturer refused a replacement (rather use dryer sheets, but I can't!) or refund without sending proof of purchase, which of course I didn't have any more. I expected them to last for years, as advertised. I was willing to send the broken ball, but that wasn't enough "proof of purchase." Ridiculous and a rip-off.Beyond the issue of durability, they are certainly a poor substitute for fabric softeners and dryer sheets. I never noticed a reduction in dry time, either.