Both the collars and remote work very well. All the devices are rechargeable and both collars can be adjusted for a wide range of neck sizes. The collars are reflective and you can turn on a flash light for both the collars and the remote. The remote can also support a third collar (sold as an extra). The range is good too but may have interference with buildings that are metal.
The collars have static, vibrate and tone. I personally don't use the static but the tone is very useful if you teach your dogs to recall to the sound. The vibration option is good for dogs who are hard of hearing or really sensitive to correction/sound.
The only frustrating thing about the product is that you have to put the collars together, including the snap clips and that took me a minute, but it wasn't terribly hard .