The unit should be able to tune in to any unencrypted channel, whether it is standard or high definition. The quality of the output will depend on what kind of display you use. Through the HDMI output the unit will upconvert to 1080p, if the display can handle it. Upconversion is only an approximation, and will not look as good as a true 1080p source signal.

However, the unit can only record standard definition to the DVD (480i), since that is what standard DVD is, as a format. In other words, if you tune in to an HD signal you will only be able to record up to 480i to a DVD.

DVDs may take up to 20 minutes to burn and finalize, but it depends on the brand of DVD media, and if you are filling the entire disc with data.

I have had the recorder for over a year. Mine does have an HD tuner but downscales the video. It picks up the available HD channels from cable and also the HD and digital channels over the air if I add an antenna. Looks great on my 50inch plasma and better than the live digital station. Only issue I have is that the HD channels move around on this tuner so I can miss weekly recordings. Fox has moved 3 times on this recorder while the same station on my HD set's tuner has not moved. NBCHD is 15.1 on my TV and 15.2 on the recorder this week. Last week it was 15.1 so missed recording ER for my wife this week. I should also note that mine has a silver DVD door and could be a generation before this unit but has the same model#. Shows recorded with the digital tuner are a bit darker in terms of the contrast while shows on the HD and NTCS tuner are fine.

If the show you are converting from the HDD to a DVD will fit to the DVD it transfers pretty fast simlar to 4X on a PC regardless if you have an 18X DVD in. However if the program is to big to fit on the DVD, it will take you about 30min longer than what the program is. The reason being is that it plays the program and rerecords it to the HDD in a lower resolution (LP, EP etc) and then burns it to the DVD. I record in SP to the HDD and the picture looks fine on my 50inch plasma. I also upconvert to 1080i.

Yes! Once you do a channel scan to allow the tuner to memorize all the channels, you will be able to program the machine just like a VCR to record all your favorite programs from over-the-air digital broadcasts.
It does take a while for the scan because it goes through (scans) 125 analog channels and the 135 digitial channels. This could take up to 15 minutes.

You do not need to have your TV on to record programs. The unit has its own tuner. You can also watch a DVD on this unit while it is recording to the internal hard disk drive.

As Gizmom stated it is very easy to edit out commercials. What you do is split the show at the commercial break and then again when the show starts back up. Thus you have isolated the commecial break into its own program and simply delete it. It's best to burn your DVD right after doing all this and then delete the program pieces. The content tables of the hard drive not to mention the fragments you create by doing this can slow the machine done and could eventually mess up some recordings as the drive fills up.

One way to look at this is that the 2160 can select only one video input source (NTSC, ATSC, L1, L2, or L3) at a time, but can view a DVD title, HDD title, or video input source while recording. Thus you can record one of the video inputs while viewing from the DVD or HDD, but you cannot view one video input while recording a different video input. You cannot change the video source or channel while recording is in progress. You can view a previously recorded title from HDD, for example, while recording another. The autostart buffer does allow you to pause and move around a given video input while it is recording.
If you want to view one TV channel while recording another, the TV must use the coaxial RF pass-through and tune the other RF channel directly. If the channel is DTV, the TV must have a DTV tuner or a converter box in the RF link. The coaxial RF pass-through does not interrupt or substitute the signal coming from your antenna. The 2160 (recording channel) output does not appear on the RF pass-through output, freeing your TV to tune a different channel.

Yes it does.

Quality from best to worse ...

HDD
HQ ... 33 hours
SP ... 66 hours
SPP ... 82.5 hours
LP ... 99 hours
EP ... 132 hours
SLP ... 198 hours

DVD
HQ ... 60 min
SP ... 120 min
SPP ... 150 min
LP ... 180 min
EP ... 240 min
slp ... 360 MIN

Yes, it has a 'Pause Live TV' button on the remote control. As long as you are watching your show through the DVDRs built-in tuner, you just press this button and it starts recording in a large, temporary buffer. Then you can go answer the door, phone or nature call. When you come back, you simply press 'Play' and it will start playing right where you left off. You can then skip through the commercials and watch your show to the end WHILE it's still recording in the buffer (until you catch up to LIVE real-time. It's actually really handy!

This unit only has one tuner, so no. From the reviews I have read it appears the instructions, and the remote are not as user friendly as other productions on the market. My guess is that if your VCR is an older model and you are used to setting the programming NOT by putting in the VCR+ code, then you will be fine.

Yes. It has various inputs (like standard RCA cables and s-video cables).