Review on 4-Pack 3.3V 5V FT232RL USB to TTL Serial Converter Adapter Module for Arduino by Danny Badasz

Bought four, all with the same serial numbers. I've tried flashing it with FTDI software but it's clearly ROM encoded. The devices will work with Windows, but their COM port number will change depending on which USB port you plug them into. I have Linux in VirtualBox and only the first one is skipped and assigned to port /dev/ttyUSB0. All others will not participate.