My three products from Target arrived less than four hours after I placed the order with Google Shopping Express.
Two individuals wearing apparel with Google Shopping Express logos walked up with my purchase, scanned it upon my acceptance, and got back into their Toyota Camry. The car didn't have any Google logos, and the workers said they were going back to Target to wait for more orders. Mine was the last one in that delivery window. Neither member of the delivery team knew what was in my package. They said someone else pulled it from the shelves and packed it.
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My Amazon order showed up at 7:21 p.m., according to the tracking information online. That's almost 12 hours after placing the order, but it was within the promised delivery window.
In the end, I got the products I ordered from each of the retailers, and yes, within the same day. Yet, Google Shopping Express was much easier to navigate, and the entire process was fast, from order to delivery.
Amazon's same-day shipping wasn't easy to navigate, nor was it really speedy.
I would declare the Google Shopping Express the winner of the two, based on this one, limited test. But I'm not sure same-day delivery is really all it's cracked up to be.
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If I really needed that toothpaste or shampoo, it's a lot faster to just run to a drugstore. Amazon has retrained my shipping expectations, and as an Amazon Prime customer, in a city that gets deliveries quickly, I'm not sure I would pay the extra $5.99 to get it same day, when my prime membership usually gets me orders in less than 48 hours.
Maybe it's not really about whether it's useful, but whether it's possible. And both proved, it is.
—By CNBC's Courtney Reagan