hey all,
I registered to this forum just so I could reply here as this thread has helped me too

a friend of mine requested my help in helping him convert his 20gig hdd to 120gig. all we could find was a 160gig hdd and so we ordered a WD scorpion blue 160GB disk, which should have been bevs, as the site we ordered from stated, but ended up getting a bevt. first few minutes I told him that I think it would be best to return the HDD and keep looking for a bevs, but seeing as how people succeeded with it we got bold and adventurous thus we kept going and so I found hddhackr version 1.11 which solves 99% of the problems.

it supports ... wait , let me paste what they write, better , no?!

--------------------------------------------------------------------------------------------
(v1.11)
* Fixed issue, that sometimes caused flashing of Model Name to incorrect offset.

(v1.10)
* Added option to create Partitions 0/2/3 (no more manual hex editing)
* Bug fixed, that caused errors like "LBA size does not match"
* Improved compatibility
* Minor changes

(v1.00)
* Completely new version core
* Two flashing modes, Auto and Manual
* Western Digital Vendor Intro Power Brute for misflashed drives
* Minimized incompatibility problems
* Improved exception handling
* Confirmed HddHacker supports
- WD Scorpio Series BEVS/BEAS
- WD Scorpio Blue Series BEVS/BEVT
- WD Scorpio Black Series BEKT/BJKT
- WD VelociRaptor Series
----------------------------------------------------------------------------------------------

and so I can confirm that the auto mode did everything, created undo files, partitions, recognized the hdd as wd and so on, maybe the tutorial need some revision?
plugged it into his xbox, formatted it, as instructed by me, he played a game and saved. all worked fine. then I went on with transferring the data between the two hard drives.

personally I prefer the xport 360 program, I used version 2.03 and it's awesome in comparison to the other things recommended here and in other places, we tried the other ones and they didn't work well, plus xport 360 tells which file is connected to which game. I did a full image backup for him, so he has all files on his computer and in case of need can restore what ever he may need to the new hdd, that way he also have all the files on his pc in case I forgot to transfer something or HDD gets corrupted for any reason.

good luck y'all

p.s.
about corrupted saves talked about in previous pages, there are games that won't let you transfer saves no matter what, one list I found on the net stated the following games:

UNMOVABLE SAVE GAME FILES:
Ace Combat 6 (can move but not copy)
Call of Cthulu: Dark Corners of the Ear
Crimson Skies
Dead or Alive 4
Fable: The Lost Chapters
Ghost Recon 2
Indigo Prophecy
Perfect Dark Zero
Raze's Hell

I do know rockband won't let you (I bought a new console, used the old hard drive ,bought an arcade which comes with no HDD as i already had one, and saves did not work anymore) and I've seen somewhere that burnout 3 won't let ya either