Well, my verizon cap is 18000 feet from the CO.

So 768 is the physical limit for me.
As for Comcast, I'ld give them a try. No commitment sealed it for me. I can try to live with their DVR, and if I can't I'm not out anything!
Oh, as for simular channels (per your PM), Discover and TNT-HD were nearly identical from V* to C*. ESPNHD looks better on C* then it did on V*. OTA looks better on V* (duh, true ota having more bandwidth, I bet.).
-John
PS> Maybe you'll get lucky and get a good Moto box. Sounds like some areas have rolled back to the old single tuner Moto box because of problems with the dual tuner model (or just short supply).