The Lenovo Flex has an HDD storage medium which is better than most laptops that are a similar age to it. Most 2 in 1 laptops that were launched around the same time as it have an SSD storage medium. HDD is a traditional storage drive which stores the information on magnetic disks. HDD drives are slower than other forms of storage such as solid state drives (SSD) and flash drives.
This portable PC's storage medium (HDD) is actually the worst storage medium across all 2 in 1 laptops that have been around for a similar time to the Flex.
An SSD storage medium is the best storage medium across comparable types of portable PC.
If the storage medium of this portable PC is not good enough for you then you might want to consider the HP 13-r100dx (£1,054.30) (Hybrid-HDD).