While still a E* customer (since 1998), we only use DISH for SD channels/DVR. We got Comcast to try out their dual-tuner DVR. We use them for their HD offerings....
very happy with what they offer, and the Motorola DVR is really nice! This was also a cheaper way to go, since it just costs $10 to rent the DVR, and HD channels are included with digital cable. We get $25 off each month from an old D* box I gave them [Dish buy-back program].
We get these HD channels: ABC, CBS, NBC, PBS, FOX, InHD, InHD2, ESPN, Comcast SportsNet, DiscHDT.
If we subscribed to premiums, they offer HBO, Cinemax, Showtime, Starz in HD.