* Illustration: Christian Montenegro * Jon is shopping for Ben & Jerry's vanilla ice cream — nine pints of it. And all need to have rolled off the same production line, on the same date. He enters the supermarket carrying a Styrofoam cooler full of dry ice (to keep the ice cream cold), a pair of gloves (to keep his fingers warm), and a flashlight (to help him see the inkless indentations on the bottom of each container that show where and when it was manufactured). Reaching the freezer section, he sits down and begins stacking ice cream on the floor. "Eventually a stocker comes over," Jon says, recalling the incident. "He's not happy."

Jon is not his real name. He won't reveal his true identity because he is a member of an underground network of nine full-time and 85 freelance shoppers working for Consumer Reports. In 2006 (last year's numbers aren't available yet), CR tested 3,377 products, drove 85 cars, purchased 572 tires, washed and dried 192 wrinkle-free shirts, and prepared 470 pounds of mashed potatoes. According to the magazine's rigid ethics code, it all has to be bought by secret shoppers. The cost is considerable: In 2006, the advertisement-free magazine spent $2,849,349 on cars alone.

Making these purchases without saying why can be tricky. Once, Jon told a phone salesman that he needed a particular model because his mother had Alzheimer's and he'd never be able to teach her how to use a new brand. He laughs when he describes the wary looks he got after filling up a shopping cart with condoms. He fondly recalls the time he purchased five different washing machines, claiming that his landlord father had given tenants their choice of brands.

But Jon's favorite story by far is the ice cream. With pints stacked on the floor and an angry stocker looming overhead, Jon had to say something. "So I go into my Rain Man routine," he says. "Count the vanilla, count the vanilla, gotta count the vanilla.' Eventually, the stocker just gives up and walks away. And I get my ice cream." Once products are purchased, they're taken back to Consumer Reports' Yonkers, New York, headquarters, where the magazine maintains 50 tricked-out, cost-is-no-object laboratories. There are labs where trained tasters sample chocolate, labs where air conditioners are evaluated to see if units are more efficient at blowing cool air to the right or to the left, and labs where strollers are pushed over a series of bumps for hours at a time.

In the case of the ice cream, the pints are handed off to the magazine's sensory group. They'll be just as scrupulous in the testing as Jon was in the buying. "We put things in our mouths that you wouldn't normally put in your mouth," says group manager Maxine Siegel. "We'll use a penny to get a baseline for a metallic taste, Crisco for that fatty mouthfeel, cornstarch mix for a chalky texture. We'll chew on birthday candles to get a sense of wax." That way, she says, "everybody knows what they're talking about."

One down, 3,376 more products to go.

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