pringy sole.The rival shoes are so well-matched that they

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It has taken off as a fashion shoe. The massive Air bubble at the heel gives Nike a way to inject a big, bright burst of color and energy in the design, and the company has released numerous version that mix and match colors across the upper and the sole.It took Nike’s chemists, engineers, and designers more than three years to develop React, a running platform that has the cushion and bounce of a very firm marshmallow. The company had big plans for it when it debuted the shoe in January. Brett Holts, Nike’s vice president of running footwear, told Quartz they expected it to quickly become one of their biggest running platforms, and to essentially replace its predecessor, Lunarlon.Comfort is a top priority for shoppers today, making React appealing to customers whether they plan to run with it or not. Nike, in fact, is in the midst of launching a new iteration designed for everyday comfort—and style—the Nike React Element 87. Nike again turned to Paris Fashion Week for the shoe’s debut, working with Japanese label Undercover. But it has also started selling non-collaboration versions of the React Element 87.

They were already beginning to appear on the feet of guys at the Paris men’s shows last week.Though one important point to note about all three of these sneakers is that they aren’t just appealing to men. “The success of our new cushioning platforms is driving momentum in our women’s business as well,” Parker said on the investor call. “In fact, following our launches the past three months, the 270, VaporMax and Epic React are already the top three selling women’s athletic footwear models, above $125.”It took Nike chemists, engineers, and designers more than three years of development before the company was ready to release its new Epic React shoes this past February. The first running shoe to combine Nike’s React cushioning platform with the company’s signature Flyknit uppers, it made for the lightest and bounciest Nike shoes yet, and gave the company a new way to compete against its biggest adversary, Adidas.

Adidas had introduced its own big innovation in bouncy soles, the Boost cushioning platform, in 2012. Since, it has become one of the company’s signature products, and the focal point of Adidas’s successful UltraBoost line of running shoes, which similarly features a sock-like knit upper paired with a squishy, springy sole.The rival shoes are so well-matched that they raise an inevitable conundrum for shoppers: Which one is better?Tiffany Beers, a longtime engineer at Nike who left the company in 2017, set out to answer the question—and created a 12-point checklist that makes a pretty good guide for rating any pair of running sneakers. Her criteria include stats that affect performance, such as weight, but also things that matter to the average consumer, like price and the ease of adjusting the laces.