I mean flash memoryI've never had a bad flash drive although I agree it is best to purchase a quality brand flash drive.
It's normal for flash drives to get warm when in use or when under heavy use.
Flash drives that get hot enough to release an odor are close to death and should be trashed.
I like Lexar and PNY flash drives.
San DiskHow is the flash memory installed.
Is it removeable / replaceable.
What type of flash memory is it.
If the flash memory is soldered to the board then you are SOL.