The DELL XPS 13 l322x has an SSD storage media which is better than the HDD storage media found on most notebook PCs of this type and age. Solid State Drives (SSD) store data in semiconductors on a circuit board rather than using magnetic or optical media. Solid State Drives have no moving parts which makes them very fast and reliable.
An SSD storage media is actually the best storage medium across all notebook PCs that came out more than two years ago.
The worst storage medium across similar types of laptop is HDD.