7 of 10 people found the following review helpful
If you own the 360s 4GB...,
Verified Purchase(What's this?)
This review is from: Xbox 360 Data Transfer Cable (Accessory)
...then you do not need this cable. If you purchase the 250GB hard drive upgrade, then you will have both the 4GB memory unit and the 250GB hard drive available for use. You can transfer data directly between the two--you do not need this cable.
I state this because the instructions with the unit are not clear. I am surprised that Microsoft would not see how financially rewarding this upgrade path would be...