I have also used Kongs for years with no problems at all. Generally, the ferrets just hide them as another toy. Occasionally a rescue will chew on them, leaving just teeth marks in the toy. I have all sizes, from the smallest to the largest and haven't had any problems. I do have only the Kong brand though, as some others are a softer rubber. Debbie, Kindness Matters Ferret Rescue Check out our auction / raffle sites to raise ferret rescue funds. Plenty of non-ferret related items too! http://fbogkmfra.blogspot.com/ Be sure to click on Older Posts to see all the auctions! http://fbogkmfrr.blogspot.com/ [Posted in FML 7195]