You raise a good point Mike, one which I have seen before.
It reminds me of the long threads about whether you get less artifacts with 8 bit 4:4:4 processing or 10 bit 4:2:2 processing. I think I've developed a permanent squint looking for the difference but I've convinced myself there are fewer problems with 10 bit.
I can see the difference between MPEG decoders. On the Oppos, hdmi720p using the FL2310 decoders in the 971/981 looks better with less grain and artifacts than the Mediatek decoder in the 970 at same resolution. I've played with all the Oppos and looked closely at them on my 720p projector and 1080p display. Where do you want to do the interlacing and upconverting, at the player or in the display? Same issue we were discussing above with audio and with the same answer, it depends where you have the better chip, circuitry and processing.
I know people concern themselves with jitter and loss of data in digital transmission but I doubt that's an issue with the better designed players, dvd or cd. Most of the internal firmware in these things has sophisticated error correction algorithms to deal with that potential problem, so how many ones and zeros can you possibly lose anyway? In that regard, I had fun with some fellow audio enthusiasts last winter to see if we could hear or see any difference with uncompressed copied cds/dvds. Needless to say no one could tell the difference and the guy who swore he could tell the difference ended up buying the drinks.
Whether the Oppo mod is worthwhile depends on how good your display is at video processing. Most good players like the Oppo have better chips/processing than most 720p/1080i displays I have seen. On the other hand if you use a 1080p display or plan to buy one eventually, it may be more productive to let the display upconvert to 1080p and run the 970 at hdmi480i.
While it may not be representative, I thought the upconverted 970 hdmi480i image wasn't as good as the the 971/981 hdmi720pimages. That was also confirmed when my ISF guy scoped the 970 hdmi480i with his accupel and there were some strange jiggles on his test patterns that weren't there at other resolutions. So I sold it.
I'm about to spring for a Toshiba hd-dvd XA2 because Toshiba has implemented that killer Gennum chip into its processing.
