I have 2 single tuner Tivo's. One on lifetime service. The other I receive the multi-service discount. I had the following problem on my lifetime unit: I kept getting the Welcome Powering up screen, then the Almost there screen...then the GSOD would show up for about 1 minute before it would reboot and start all over again. Once I unplugged the unit it became stuck on the Welcome Powering screen. From what I have read it appears I may have a bad hard drive. My question is can I take the hard drive from the other unit and put it in the lifetime unit? The reason I am considering this is I was just about to purchase a Tivo HD machine and I was going to cancel the service for the Tivo I pay a monthly fee for and use the Tivo with lifetime service on our 2nd regular TV. Then I would be able to get the multi-service discount on the new Tivo HD box. Hope this makes sense.