Here's a test from 2018
https://www.bikeradar.com/features/b...ted-and-rated/
I had the acid flash fade Evade helmet for two years. My LBS had it on sale because it was a Large, Ugly Color, and the clasp was a magnetic one instead of the standard snap one so nobody bought them and I got a great deal. It was the most comfortable helmet I've had. Wearing it back to back with another less "aero" helmet on a hill close to my house I could really tell the difference in wind noise going down the hill. It was striking in that manner. No clue if it made me "faster". I'm an old fat white Fred so I looked completely stupid wearing that helmet. Luckily nobody pays attention to what mediocrities like me are wearing so I didn't get made fun of or anything to my face. But I looked dumber than normal particularly since it was a size large. Sold it to a new owner who probably is faster for wearing it.
If anyone asks, I'd recommend the Evade over all others.
Here's a more recent "study" for some more "data".
https://www.cyclingnews.com/features...cling-helmets/
I went with a MIPS helmet with ANGI (piece of mind for my wife) and a size medium so now I only look 89 percent ridiculous instead of 113 percent ridiculous with an Aero helmet.
Here's some articles and videos (some with actual testing) showing which things for road cycling make you faster and it breaks it down my costs per watt. I think, IIRC that a helmet was up there but certainly not as good as wearing skin tight clothing and getting into a better more aero position on the bike. Wheels were high up there, but frames were not. Shave your legs, that will make you faster too.
https://www.torhans.com/pages/dollars-per-watt
https://www.shopforwatts.co.uk/blogs...watts-it-worth
https://m.youtube.com/playlist?list=...J-soSCDKCKR97t