The DELL XPS 13 has an SSD storage medium which is better than most medium processor core laptops that were launched more than two years ago. Most laptops that are a comparable age to it have an HDD storage medium. 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.
This portable PC's storage medium (SSD) is in fact the best storage medium across all laptops of this age and spec.
The worst storage medium across similar types of portable PC is HDD.
It may also be worth considering one of the alternative notebook PCs that have an SSD storage media currently available including cheaper laptops such as the DELL Latitude 12 E7250[plb_2367862_price], or the HP EliteBook 820[plb_2746818_price].
If you are looking for a notebook PC with a better storage medium then you might want to look at the HP Pro[plb_1496960_price] (SSD), or the DELL XPS 13[plb_2417241_price] (SSD).