Wearer of Vaporfly's wrote:
Spikes are faster for the track. The 4% are marathon shoes. This puts her at 29:55 IMO. The shoes are not grippy at all.
The 4% shoes are best for the 10k. I've experienced it. In the marathon and half, the bounce is gone after 10 miles. I've seen unreal 10k PRs with the 4%.
Look at Flanagan when she ran her indoor 3k in Seattle- in the Vaporfly 4% with a spike plate. Same for Infeld at Usatf and worlds last year. The shoes work on the track.