Hi all, I have 2 Tivo Premieres (one XL, one Standard) arriving this week and I've got a Comcast appointment to install the Cable Cards on Saturday. My question is whether I need to make sure they have Tuning Adapters for my Tivo's. Both TV's are HD, with HDMI. I live in Novato, CA. My Comcast office is in San Rafael. Is there any way to tell if they are using SDV (Switched Digital Video) before hand? The Comcast phone rep didn't seem to have any clue. Thanks!