I use this rear light during daylight hours on my rides to and from the bike path. I travel on one very busy street and cross two very busy streets before I get to the dedicated bike path. Even though I am in bike lanes, I have seen drivers that just don't see bikers. I use high visibilty clothing and two other rear lights. The Niterider Cherry bomb is definitely bright and visible in bright sun daylight hours from a distance.
This is a great taillight for riding on the street. In flashing mode it will definitely get drivers' attention. You might not want to use that mode when riding in a group because it's pretty intense. Fortunately there are three other settings- different brightness, all continuous (not flashing) which is a minor drawback.
I use this light for urban riding in South Florida on a high powered E bike. The syncopated strobe pattern is very attention getting. It ha s normal strobe setting also for at night. Even Niterider says this strobe gets more attention than their supposedly brighter versions. It also has some level of reflector function if you forget to turn it on. Niterider makes rugged MTB lighting products. That shows in the weatherproofing and toughness of this light.
I have Niterider lights that are 10 years old and still function properly. Function, quality and reliability are what I've come to expect from Niterider products.
It is a great light for riding in traffic during the day. It is very bright and the flashing sequence is much more attention getting than a regular consistent strop. I mounted it on my seat bag and it has taken quite a few hits without falling off. The button is easy to use and very accessible without having to stop.