Hi,
We dont have any difference between USB install and Install ESXi on Harddrive. all the features and functionalities are same. You have do following additional configuration on USB install if required
- Remote Syslog configuration
- Netdump configuration or change the coredump partition to harddisk by creating additional VMKcore on Harddrive.
- Try to use the qualified USB stick (refer the Hardware vendor documentation).
Are you looking for any specific limitation other than above mentioned.
Thanks
Nithin