My girl Julip is 18 weeks today!
We have Kong's for her & just put kibble in them, as I too don't like the idea of not cleaning the inside out properly. But yes she can get the kibble out pretty fast. Once the kibble is out, she never has actually chewed the Kong?
We have a dog ball with circle indents going around the outside of it, that I put cream cheese or peanut butter IN these divots & she has to lick off (again its the outside & its in divots, so the stuff doesn't touch the floor as its more pushed in) Easy to clean after (although she does a great job!)
This ball also has a hole in it to stuff - but again rises the not cleaning it out properly, so it too just gets kibble inside.
These things keep her occupied for awhile - yay! This one she really likes
http://www.nylabone.com/product-finder/by-brand/puppy-chew.php?page=1
And this one, we have too & I can stick stuff IN those side openings, and again, its easier to clean then the strictly stuff INside Kongs.
http://www.nylabone.com/product-finder/my-pet-is/dog-small/fun-n-fit-rubber-canvas-combo.htm
Must say with her teething now, she really enjoys just a wet facecloth twisted & then turned into a donut like shape & put in the freezer. Occupies her for awhile! Chewing on it right now! Its free & safe! (Just make sure they aren't eating the fabric

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(Hope those links work - if not, message me I guess?)