This product works well. Remember to get the cord to transfer the data from your old hard drive to the new one. Wish I would have known how long the file transfer was gonna take. Took at least 3 hours. But our 120GB hard drive was FULL. The new xbox 360 slim makes you sign in with your Windows Live ID email address so make sure you know that. :) Our new xbox 360 slim is having problems with freezing, not sure if it's the hard drive or the unit. But yeah, they're not flawless.
The hard drive arrived in time for Christmas (yay!). It doesn't say in the write up but this hard drive IS compatible with Xbox E types - it even says it on the box. Installation was super easy, just plug it in and off you go.
I purchased a 4GB Xbox a few years ago. I used flash drives for additional memory but that has its limitations. I got the 320 GB hard drive so I would not have to worry about storage problems again. Installation was easy and currently I have no problems. I recommend this product to anyone that has an Xbox 360 S and require additional storage.