I have 3 direcTivo's, a SD-40 and HDVR2 and a HR-250. I have zippered the SD-40 and HDVR2 and they work beautifully. I have a couple questions before I attack the HR-250. I used Instantcake / Zipper on the other DTivos. I plan to do the same with the HR-250. In reading the forums I see information that confuses me. When the HR-250 is hacked as above, does it open up the same hacks as the other machines? Will HMO and MRV work? I am most interested in MRV, If so though, what happens when a show that was recorded in HD try to play on the other machines? Another issue is whether to use my original HD (instead of purchasing a new one). Not the $$, but losing my recordings and settings. Is there a way to avoid this? Thanks for the fast reply as I want to do this today or tomorrow if possible.