I currently own and race in a pair of Nike Rival Ds, and have raced every race in them except one race where I borrowed a teammates pair of dragonflies when I lost my spikes. In that race I set a 800m pr in like 20mph winds which I never beat. I’m curious how much of a difference racing in dragonflies vs rival ds makes. Or more generally, high end vs low end spikes. I can’t find any objective or subjective way to figure this out.