zbroke, I just did the one receiver to see if it would work.
It is very simple to swap out the hard drive itself, just some screws and the hard drive cable connector to remove. When the receiver boots with the new hard drive you need to get into the settings menu and then enter 4-9-8-8 asap, as if you wait too long the receiver will re-boot again. Once inside that hidden menu you need to do a factory reset which includes erasing the hard drive. After a few minutes the receiver booted up fine. I just had to go online and do a few re-hits on the Shaw Direct website to get all of my subscribed channels restored and getting the advanced channel list back.
So far there has been no issues with it. If there are any issues I'll report back about them.