There is one thing.At one point before Flashing there guide says
IMPORTANT! You must power the 360 back ON before pressing any
key to continue.
If you press any key to continue with the 360 powered OFF (as
instructed to do on screen) it will immediately freeze attempting to
write Bank 0. This is a bug in iPrep 006 and will hopefully be
resolved in a future release.
So power the 360 OFF as instructed on screen, wait a few seconds,
power it ON, wait a few seconds, then press any key to continue.




I did not find this to be the case with the BenQ drives I've done.
I did just what was on the screen.
The flashing i've done have work perfect for me.That is not saying that there guide is wrong(those guys know what they are doing)it's just if you can't get it to flash try the other way.
Remember read everything before you try to flash your 360 drive.If you have any question just ask and one off us will do our best to help you get the job done right.

360mods.net guide to flashing the benQ