Aldi is rapidly expanding in the U.S. Already, the no-frills German supermarket chain has nearly 1,800 stores in 35 states offering super-low prices on brand-name knockoffs. Indeed, 90% of Aldi's products are exclusive store brands, and many mimic the packaging and taste of national brands. We found several great items at Aldi that deserve a spot on your grocery list based on quality or value - or both.

But after checking in with shopping experts, as well doing comparison-shopping (and taste-testing) on our own at stores in Northern Virginia, we found that some deals at Aldi aren't worth it. First, brand-name knockoffs don't always taste as good as the real deal. Second, Aldi doesn't accept manufacturers' coupons or offer a loyalty program. That means you can find certain brand-name products at other retailers at comparable prices to Aldi's knockoffs once you factor in sales, coupons and loyalty perks. Take a look at what to buy - and what to avoid - at Aldi.

What to Buy: Baking Products

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Under the Baker's Corner store brand, Aldi was selling a 32.8-ounce bag of brown sugar for $1.29;