I have both Directv (RCA 3030 Receiver) and Time Warner Digital Cable (General Instruments Receiver) I much prefer Directv.

With the Digital cable we actually only get a few digital channels, The picture on the digital channels appears to me to be not quite as good as Directv. All cable channels under 100 are analog channels, the only digital channel I watch is Discovery Science. I do like the digital music channels which is why we have the digital cable. (We had DMX and they discontinued DMX and replaced our DMX receiver with Digital cable which I would return for DMX if I could) I like the Directv music channels too but I like having the choice of switching to the Digital cable music channels.
One think I hate about the digital cable box is that there is no way to delete channels from the channel list so I have to scroll through all the channels that I don't subscribe to or enter the channel that I want directly (makes channel surfing a pain), I see this as a basic feature that even the cheapest TV's support but for some reason this is not supported by the software on the digital cable box per Time Warner.
Overall I like the Directv on screen guide better but the digital cable does have a nice feature that my directv receiver does not have: The Digital cable has next day and previous day keys so that I can quickly see what is on the next day at the same time or the day after that up to 5 days. With Directv, it can take several munites of scrolling to get to the same time on the next day.