These shoes are awesome.
Since May 17th (about 3 months) I've run 270 miles in them and they have totally changed my running life. In general, my pace is about 30s/mile faster at the same HR, which is about 5% improvement. My recovery is much faster: muscle soreness after hard runs less, and in fact I do a lot less foam rolling and it seems I don't need it..
My Garmin 935 has a feature where when you start a run, after about a mile it tells you your "performance condition"...eg. +1 , -2 , etc. This is based on (I think) the half marathon time results (time, HR) put in as my benchmark vs what you're doing on that run.
When I wear the Vaporfly's, it regularly tells me my condition is +4, that's because my HR is very low for the pace I'm running. When I flip back to my Kinvara 10's, it's usually a -2 or more. This is pretty huge. The difference is like night and day.. ..I'm also a Strava runner and i've been breaking some of my old segments records from 4-5 years ago. I do these runs where I hit paces that I thought were long gone.
I'm looking forward to a road race soon. Probably I'll do the Quarry Lakes half. ..not a pure road race (some crushed rock) but haven't found anything better that fits my schedule. We'll see. There is also the Trailblazer 10k but not sure I'll be in town.
Stay tuned. I have also bought a pair if the Vaporfly Next %, and they are a bit different but also good. A review shortly...