The bottom line is that once you are with DTV or Dish, you get used to the DVR and yeah, one may be a little slower changing channels, etc. but unless you have both of them in your house at the same time, you get used to it.
Okay, let me tell you a little story about the final straw that made me switch from DirecTV to Dish:
I had my DVR set up to record a program off of TLC in the morning. In early afternoon, it was time for my preschoolers to have their TV time. I went downstairs, they sit down on the couch to watch their program, and I turn on the TV and DVR. There, in living color, is "A Baby Story" on TLC with lots of screaming and a very transparent oval to "cover" things. Press the List button. Nothing happens. Press the Guide button. Nothing happens. Press Channel Up to try to get away from the channel. NOTHING HAPPENS. 40 seconds after powering up the DVR, it finally brings up the program list. Another 15 seconds pass as it refuses to scroll quickly, or start playing the program. Nearly a full minute before I can get rid of something I really didn't want to have to explain to a small child.
So, yeah, you get used to it. You get used to pushing buttons and having nothing happen from time-to-time. You get used to a DVR that doesn't respond when you ask it to do something. And then, one day, you say, "You know what? It's 2012 and it's about time somebody built a DVR that was as quick as I am." I already had a DTVPal DVR for OTA, and it was blazing fast. I got a Hopper, and it hasn't let me down.
Oh, and I went through the whole thing with DirecTV where they promised me a new HD DVR to replace my old unit (which they would not admit was faulty in any way) along with a new 24-month contract. But they couldn't promise me a particular model number (we can't pick the model numbers of the receivers out there) so I would be playing receiver roulette that they installer would show up with yet another HR22-100. Or I could pay $200 to a third party and guarantee myself an HR24, but then I started reading where the HD GUI slowed even some of those down, and I threw up my hands and walked away.
Now, I've heard some people are very happy with the Genie. I've also heard that it is slower than a properly functioning HR24. Maybe it is. But I learned the hard way that DirecTV can't build a DVR that operates at a good-enough-for-my-needs speed, and they have a history of releasing firmware updates that make things worse as far as speed and responsiveness go. No thank you to DirecTV for all their "come back, we'll make it right" offers.