Vista - Install VHP x64 from eSATA drive possible?

Hi,

Is it possible to install VHP x64 from an eSATA drive like you would use a USB Flash drive to install Vista from? I have looked far and wide and I have found people looking to install and run Vista FROM an eSATA drive but have found no info on actually performing the install from an eSATA drive....

I have an unattended vista install on a USB drive setup and can successfully install it from the usb drive but being able to the install from a eSATA drive would be exponently faster, as I tend to re-install every couple of months.

I have a jmicron 36x controller and have slipstreamed the drivers into the boot.wim and I can boot from the eSATA drive but it still won't finish booting to the install screens. It hangs on the 2nd load screen (not the greyscale screen but the color boot screen).

Has anyone else attempted this or at least have any ideas?