alright, i have a fix here which i thought i would post for anyone else having the same problem
with having everything setup to flash the drive, turn the 360 on before turning the PC on, but leave the sata cable unplugged from the PC. once it all loads up, type dben 1234567 12345 (serial number) and when it asks to resend untill response, press Y. then when it comes up with 0x00, plug in the sata cable into the 360 and it should start changing between 0xD1 and 0x51. then just turn the xbox 360 off and back on and it should start reading the firmware.
now if it freezes like it did for me once it has finished reading the firmware, you will have to reboot in to windows and load up firmware toolbox and copy the key over to the iXtreme firmware. once you have done that and checked that the original firmware is ok and created at least 5 backups of your original firmware, copy the created firmware onto your USB/floppy under the folder backups/1234567/12345 (your serial number) and name the file ben-CFW.bin. turn off your PC and turn on your xbox with the sata cable unplugged once again.
now boot the PC back into DOS and once it has booted up, plug in your sata cable to the 360 and type in fben 1234567 12345 it it should succesfully flash your benq drive