Despite being ostensibly useful to IT departments and security-conscious organisations, U3 features various functions that have raised question marks by expert users. For instance, the system supposedly runs entirely from the USB stick, and this is confirmed in the licence; however in practice, this has been proved to be inaccurate, with several users reporting software being installed on their PCs.
Furthermore, U3 has been described as slow, while the repeated display of a splash screen when software is supposed to be booting has also been criticised.
As such, many users have attempted to remove U3. Note that removal of U3 is irreversible, so if you don't want to lose this facility, buy a new USB Flash Drive!