I tried that, my husky could sort biscuits she would eat from those she wouldn't on "the fly" she would spit the SD out while swallowing the others. I mixed a bag of Royal Canin (which she would eat) with a bag of Science Diet.
She always left an empty bowl with a pile of SD biscuits beside it.
BUT you can buy your Dogfood from here and get free delivery and a good discount for regular order and they often send further discount coupons.
Pet.co.nz - Shop for Dog, Cat and Pet Food, Treats & Supplies
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