We own a 3.5 year old, male Shih-Poo who is the most finicky eater. We'd find a dry food he'd like only to have him stop eating it before we're 1/4 thru bag. This went on for almost a year. We even tried sample sizes of many high-end dry foods with same result. He's had grain-free, holistic, high-quality kibble - so many brands that we were at our wits end trying to find yet another dry he'd eat.
When the newly renovated Pet Valu (Agincourt Mall/Sheppard & Midland, Scarboro location) reopened, we checked it out. The employees were very friend and extremely eager to assist us. They recommended Royal Canin's dry food for "Fussy Eaters" - a product we'd never seen nor heard of. Went home that night and Bingo, he loved it!
Although smaller, this shop does make up for that with their awesome customer service.