My initial experience

I finally had the two HR20's that I ordered two months ago installed on Saturday, and wanted to provide my initial feedback on the units. As a side note, I have had DirecTivo's (three of them) for many years including an HR10-250. I love my DirecTivos, and have probably only missed two or three recordings in the past five or so years so I do view them as near 100% reliable. But, I'm really not tied to Tivo or hung up on their interface at all.

The Good:

1) Very professional looking user interface, a nice improvement in my opinion to the very easy to use, but somewhat simplistic interface of the Tivo's.
2) Miniature TV picture in the upper right corner when your doing other things with your DVR.
3) Quality of scalers seems to be about as good as I have seen. Also, the HDMI works perfectly (so far) with my Samsung DLP.
4) No matter what you do, response time is near instantaneous. In this respect, it is much better than any Tivo I have had including 6.3, and 6.3a on the HR10-250.
5) One touch record is really nice.
6) The mini-guide is great.
7) The hardware appears to have everything it will need to greatly expand features down the road.
8) The guide is nice looking and very responsive.
9) My local MPEG4 stations look very crisp. I can't tell the difference between tham and OTA HD. Yes, I know that technically speaking it can't be as good as OTA but I believe that very few people could tell the difference without really looking hard for differences. Perhaps some areas are better than others in this respect. I am in the Denver market.
10) Although I think that the UI needs a few changes mainly related to series links, once you understand how it works it is at least twice as fast to check a long list of series links than it is with a Tivo. I had to go through my links several times yesterday on Tivos and HR20's, and once I understood how to get around in the HR20 it really was much faster than the Tivo (6.x based Tivo software).

The Bad:

1) The procedure for setting up "Series Links" is very un-intuitive, mainly just at the point where you need to hit the red button to go to the "Series Link" tab. I believe that this screen doesn't even have something on it with a red dot saying hit the red dot to go to the series link screen. Many of the other screens tell you what the various colored dots do but I don't think this one does. It's quick and easy once you know how to do it though.
2) The procedure for manipulating already existing series links is very un-intuitive. It's strange to have to first go to your list of recordings, then to your to do list, and finally to your prioritizer. Why couldn't there just be a "Series Links" option right from the main setup screen ? Since the to do list is really derived from your series links it seems strange to have to go to it first, and then back (up a level) to your "prioritizer". The prioritizer should also be renamed to "Series Links" since it really lets you do anything to a series link, not just change priorities.
3) I don't like the way that all of the guide data is lost upon reboot. Probably not a big deal for long term use but on install day, and in the few days after initial install this can be real annoying. This data should just be dumped to the disk so that it is still available after reboot.
4) Pausing live TV causes audio dropouts, at least on (0xE3).
5) The fast forward and rewind video frame rate could be improved, not bad but it looks a little choppy. This is probably a CPU related constraint, but I think there is still some room for improvement.

Overall, I really like this unit. That may quickly change if it starts missing my recordings, but for now I am very pleased with it. So far I'm 6/6 on recording and playback and this includes MPEG4 content.