I completed an A/B test last night playing the regular Patriot movie on my NAD via component cables vs. the Oppo playing the Superbit edition of the Patriot via DVI. The NAD is an older unit, and does NOT have progressive scan. Both units are stock and fed directly into the my JVC SX21 (1400x1050 LCOS), which was throwing onto a 116" 4:3 Carada Brilliant White screen.
The Oppo picture was better than the NAD, but not by a huge margin (I have always been very pleased with the NAD's picture). The differences were subtle, but distinct. The Oppos showed better details in some areas, but nothing that you couldn't live without. In a blind taste test, I am sure I could accurately identify the Oppo vs. NAD display when side by side, but I doubt I could walk into a room with a single image and identify the source.
I also did the same A/B with Black Hawk Down, with very similar results. In this movie, the text at the beginning that gives the background of the situation was more stable on the Oppo. After watching both movies back to back, I realized that both movies featured Jason Isaacs. Jason is not a household name, but he did a great job in both roles.
When I toggled the Oppo thru the various resolutions (480, 540, 720, and 1080) using the DVI button, I couldn't really tell much of a difference between them. I assume the PJ's internal scalar turned all 3 resolutions into the same resolution (upverting the 480, and downverting the 1080). I did use the PJ's "Information" menu option to verify that the resolution was changing. The SX21 has an excellent scalar, and does a fine job with just about everything that I send it. I theorize the PJ's scalar helps bridge the gap between the NAD and the Oppo. I also theorize that display units with lesser scalars would benefit much more from the Oppo. I have a 27" Maxent LCD that has a horrible scalar (HD looks good, but non-HD looks lousy), but it does not have a DVI connection, so I can't test out my theory. I would also expect that display units with a native 1280x720 resolution would prefer the 720 output setting of the Oppo. I will try to take some digital pics tonight of both players, but I am not optimistic that these will be revealing or helpful.
I had a slight lip-synch problem with the Oppo when in DTS audio mode. Switching to Dolby Digital eliminated the problem. Because I am using Coax for the audio, this may have more to do with the receiver than the DVD player.
I don't much care for the Oppo's remote, but that is no big deal since I always use the AVR's learning remote to control everything.
Considering that I spent very little on my NAD (it was an out of date demo that I purchased several years ago), the improvement is easily worth the $200 price of the Oppo. However, if I had an expensive DVD, I would probably be inclined to wait a few years for the HiDef DVD players to become affordable. Now I just need to decide if I want to have Wayne mod my Oppo, and if I want to try it with a DAC to serve up my 2 channel as well.