“It allows for me to be a more efficient runner,” says Iman Smith, 38, a former Army sergeant turned full-time runner, who ran a 3:10 in New York, shaving 40 minutes off his previous PR. Even though Smith acknowledges his intensive training had a lot to do with his performance—a low-mileage week for him is about 40 miles—he says he can’t imagine racing without the 4%. “You’re not thinking about the shoe. Typically when you’re running for an extended amount of time, at some point you’re always thinking about the shoes. You’re thinking, My feet are hurting. Am I getting blisters? I’m starting to feel the ground under my feet. [But in the Vaporfly 4%] I felt like I could literally run forever.”Nike does have a third shoe in the series, the Zoom Nike Air Max Tavas Damen Nike Air Vapormax Damen Fly, Nike Air Max Tavas Damen which is truly Nike Air Max 90 Mens widely available, uses a more standard midsole foam, called Lunarlon, and retails for $150—a quarter the price of the Elites, but without the Zoom X foam that could trim your race time.

“We wished we had more stock to fulfill demand, since we’re able to sell through our inventory pretty quickly,” says Wil Cramer, the general manager and footwear buyer for Brooklyn Running Co., in New York City. Cramer wouldn’t reveal just how many pairs of the Vaporfly 4% the shop had sold, but said requests for replenishment by Nike were based on availability. He also confirmed that Nike would be releasing a new colorway next spring 2018, and that his store was already booked to get some—although he wouldn’t say how many.

David Boutillier, CEO of the Fleet Feet Sports branch in Rochester, New York, says he was in the same boat. His Nike Air Max Thea Donne Nike Air Max 90 Damen store, which Nike Roshe Run Damen stocked sizes 6 to 13 of the 4%, sold out of the core sizes almost immediately. They most recently scored a restock two weeks ago, which had sold out by the time this article was published.

Shawn Marlovits, owner of the Fleet Feet Sports branch in Hoboken, New Jersey, said he didn’t believe his store had the opportunity to bring in the 4% at all. “Regardless of hype around a specific shoe, there’s a lot of decisions that go into bringing the shoe into our store. Every single Fleet Feet is locally owned,” he says. “Nike generally picks the higher-profile stores, especially for a limited-distribution option like the 4%. But honestly, we didn’t have many requests for them.”

Still, Nike’s senior director for global running footwear product, Bret Schoolmeester, tells us the brand is “keen to get as many of these shoes to Nike Air VaporMax Donne runners Nike Air VaporMax Damen as Nike Air Presto Damen possible”—a Nike Air Max 90 Damen Rosa statement that left us pondering the meaning of “as many” and “as possible.”