My experience with Dish's customer service is much worse than with D*'s so far.
1. About a year back I had some issues with my 625 DVR with Dish. I talked to 3 different level 1 techs who told me both tuners were working, when I told them it wasn't and even went as far as to read off the fact that the 129 satellite was not coming through on tuner 2. The last one was no help so I asked to move to higher support. She said she couldn't do that because she had solved my issue. She hadn't. I then asked for a supervisor, was told she couldn't do that. Finally I said "I want to cancel then." She sent me directly to retention, I told them my problem and was immediately sent to level 3 tech support.
2. When I originally ordered I wanted 1 622 and 1 625 DVR. The guy showed up to install and brough 1 622 and 1 standard definition receiver. I told him that wasn't correct, he said take it up with customer service as I have nobody I can call to verify the order. He installed the 622 and the SD receiver in the location where I wanted the TV 2 output for the 622, never running the cable to my living room for the 625. I called support, they said they would come out with the 625 the following week (another day off work). The guy shows up, sees the cable wasn't run, and was, understandably, a little pissed off (he was only doing a swap out, not running cable). Dish wanted to charge me to run the cable, I said no way. You guys didn't install what I ordered. They finally waived the fee and came out after I threatened to cancel.
Now lets fast forward on to DirecTV.
1. I didn't get my AM21's I was promised with my install (they never come with installers, the person who sold me screwed up). I called D*, told them the issue, they immediately overnighted 2 new AM21s for free ($100 value). They apologized.
2. I realized I wasn't getting superfan for free, something I expected when I signed up. Once again, called up customer service, told them my issue, the girl put me on hold for 30 seconds then came back and said I now had superfan for free.
Thus far D* has been very courtious, professional, and solved all of my issues.
IMO, after going from Time Warner to Dish to DirecTV, there is no comparison. DirecTV has won hands down.