The Transformer Book T300 Chi has an SSD storage medium which is better than the HDD storage medium found on most notebook PCs that were released around the same time as it. 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 medium is in fact the best storage medium across all medium processor core notebook PCs that are a comparable age to the Transformer Book T300 Chi.
Across comparable types of laptop the worst storage medium is HDD.
If the storage medium of this notebook PC is too bad for you then you might also want to consider the T420s (SSD), or the X1 Carbon (SSD) both from Lenovo.