I have two 500 GB Seagate USB drives. One is in an external enclosure I bought and the other is a FreeAgent. I like the Seagate for the 5 year warranty.
The 3 time move limit is moving it between receivers, this is something that is supposed to be changed to unlimited if a future software release.
You can move the contents of your receiver to the external drive and back as much as you want.
You can not record directly to the external drive, you must record it to the receiver then transfer it. You can transfer as many as you want, up to the limit of the external drive. It will transfer them one at a time until it is done or you cancel it. If you cancel anywhere in the process, nothing will be transfered.
You can watch directly from the external drive but you can not transfer anything at the same time.
The only trouble I have had is the FreeAgent drive going to sleep. This is supposed to be fixed in an upcoming software release. Even so, it never goes to sleep while you are watching or transferring something. When it does go to sleep it will either not show anything on the USB screen or it appears to take commands but not work.
I have heard some posters say they must reboot the receiver but all I have ever had to do was unplug the usb connection to the receiver. I use the front connector so as to do a quick reset when needed and also so I can plug in the other drive when needed.
Horseshoe