usb flash drive security

Clarifications

Witch hardware encreption is more strong FIPS 140-2 ENCRYPTED USB or FIPS 197 ENCRYPTED USB ?

DES is FIPS 140 certified, and AES was created for FIPS 197. AES was intended to replace DES.

However, you are mostly asking the wrong question. 140-2 is meant to describe a hardware/software paired product, and AES schemes are found under 140-2. What you really need to look at is the actual encryption methods and choose between them, not which FIPS they may or may not have been certified under.