Does it work with any flash drive provided that it's fast enough?

Yes, it's quite simple too. Just copy the contents of the DVD directly to the flash drive (or USB hard drive) and boot from it. Nothing special or difficult to make it work.

it works quite well, and the USB drive boots noticably faster than the DVD

however installing from DVD extracts the OS image from the DVD onto the intended folders harddrive

installation from USB drive copies the image to the a temporary folder on the harddrive

BEFORE extracting it into the intended folders on the harddrive

this leaves the overall speed increase open for debate

of course it is very useful if you want to change your unattend xml or modify your configuration set easily

Yes, it's quite simple too. Just copy the contents of the DVD directly to the flash drive (or USB hard drive) and boot from it. Nothing special or difficult to make it work.

Other than that I don't have to do anything special to get Vista to work?

You need to check the Windows AIK documentation on WinPE for more info.

You need to format with DISKPART I believe or it won't work. In DISKPART run these commands

select disk 1 --------------------------------------------- MAKE SURE THIS IS YOUR USB DRIVE FIRST: list disk TO CHECK

clean

create partition primary

select partition 1

active

format fs=fat32

assign

exit