OK. From personal experience, I opened up one of my 360 hard drives, took out the little hard drive inside, hooked it up to the sata port on my computer, after having to buy a sata power cable as well and then transfered everything to my pc. The problem is, it's not as easy as dragging music. I used Xplorer360 to copy all the files and then reformatted my hard drive. When I dragged everything back on there and turned my xbox 360 back on, it said my profile was corrupt. You can't actually tell which save belongs to which game. It's all coded. For instance: One save file might be named 202053108105810865454dfd5fdf5d15df. There is a folder called content which saves all of your game saves and downloads from xbox live. That is the folder that you need to keep in order to do any transferring. It wasn't too hard once I figured out that copying everything back on there, cache, etc messed it up. You also have to remember that there are 3 partitions on the drive.
I don't know anything about the new kits they have because I'm old fashioned and would rather save money by doing it the hard way and learning how things work, than dishing out 40 or 50 bucks for two connectors that cost like 8 dollars together: Sata Cables.
Well good luck to anyone who tries this. Hope this helps.