I got my 622 delivered via UPS on 2/15. The install date was yesterday, 2/22. I had unpacked and had the 622 ready to go the day it arrived, but couldn't do much till the installer changed by old style switches to the DPP models. After the DPP44 was installed on 2/22, I unplugged the 501 and replaced it with the 622. The install tech called Dish's CSR to have it activated.
Ran into a CSR who was insisting that they install a Dish 1000 at my NJ location. I already have a Dish500 facing 110/119 and another wing unit facing 61.5. Installer was trying to explain to her that it would be impossible to pick up the 129 location from here, but she kept saying, "Some of the HD channels will not be available anywhere but 129." I tried to talk to her, but the tone of her voice said, "Why would an ordinary customer know more than me?" The installer finally asked her to activate the 622 as installed, and if anything was missing or needed updating he'd work with me to install the Dish 1000. (We agreed offline that it wasn't really needed, but anything to get past the gatekeeper.)
After that everything went as expected. It took about 15 minutes for the 622 to do a fresh download, get updated EPG info and a final reboot.
The only problem I noticed so far (in about 4-5 hours of viewing) is audio break ups on a couple of channels -- HD Sat Local WABC and HD Sat Local WNYW (Fox). In both cases the problem disappeared after a while. On Fox it was during American Idol between 9PM and 9:45PM. There were no problems between 9:45 and 10PM. Did not notice this problem on any other channel HD or SD; via Sat or off the air.
Coincidentally, both are 720p channels. Can everybody please note the channels on which they're seeing the audio breakups? Perhaps there is a pattern to the problem.
SInce this is my first HD DVR (had a 501 and 301 before; returning the 301) I can only compare its HD performance to the off-the-air reception on my TV. I think the 622 has a better tuner than the Mitsubishi WD-527525 (from Oct 2004); it pulls in more channels and more consistently. It had no problems with pulling Philadelphia locals (~60 miles away). The picture quality is off a little bit on the 1080i channels
(most likely due to HDLite-ing), but is only noticeable via quick back-to-back comparisions. Audio performance is good except during the annoying break ups as noted above.
Did not really get a chance to test timer recordings, etc. I set up some for overnight triggering, lets see how they go.
A bit about my configuration: Dish 500 facing 110/119 + Dish 300 facing 61.5; DPP44 connected to a 622 (with line separator) and a 501. 622 connected via Optical Fiber audio (Dolby Digital + PCM) to a Denon 2802 AVR; via HDMI to a Mits WD52725 HDTV; a ChannelMaster 4221 UHF Antenna connected to the 622's Off-air Antenna-in port. 622 connected to a phone line.