My absolute favorite work-for-your-food toys I use are his Kong Wobbler, a soccer ball that holds and dispenses about 1 1/2 cups of foods, and his favorite Busy Buddy Tug-A-Jug I got on clearance for $3. The Kong and Tug-A-Jug both hold about 2 cups of food and take him usually 20 - 30 minutes to get all of it out, he's faster with the Tug-A-Jug which is why he likes it more but I like the Wobbler since it's a bit slower.
It would probably take a smaller dog a lot longer with those toys but Mishka pretty much just puts his whole mouth around them and drops them to get food instead of pulling on the rope or hitting it. It still wears him out, though, but I also love playing hide-and-seek in the living room with his kibble, taking him outside and just throwing a meal on the grass for him to sniff out (takes an hour), and training with him. He knows at minimum 35 commands already since we train every day to keep his mind stimulated. There's so many ways to feed and keep them busy than just putting their food in a bowl.
