Devices with stereo speakers deliver sound from independent channels on both left and right sides, creating a richer sound and a better experience.
We consider a lower weight better because lighter devices are more comfortable to carry. A lower weight is also an advantage for home appliances, as it makes transportation easier, and for many other types of products.
The device comes with its own special case or pouch, which is useful for safe transportation.
The in-ear device is ultracompact and lightweight, with little or no interference with earrings, spectacles, hats, or hairstyles. It is inserted in the ear canal itself and blocks out a lot of environmental noise. It has stronger bass tones and is unlikely to fall out of the ear.
A long cable ensures more freedom of movement.
An L-shaped plug is better if the jack is on the left or right side of the device, so that the cable isn't bent, and is less likely to break when the device is in your pocket.