It's of course impossible to say anything definitive about the Model 997's video performance without having a Model 997 in hand, but since it is using the Reon chip we can make some approximations. If you look at my
BDP-80 review, I talk a bit about the differences I saw between the BDP-80 outputting 1080p and the BDP-80 in source direct mode with an Onkyo PR-SC885. The 885 uses the Reon chip, just like the 997 will.
I didn't say anything about how the Reon-scaled image compared to the BDP-83's ABT2010. I have found a slight preference for the ABT2010 over the Reon, going back to my time with OPPO's DV-983H. If I had to choose, I'd prefer the BDP-83 to the BDP-80/Reon combo, but it'd be a close-fought thing. As for whether the 997 would "degrade" picture quality from the BDP-83, I wouldn't expect it to. Again, it's impossible to say without actually using one, but we are dealing with digital video signals here. The potential for video switching to degrade an image used to be a real issue with older analog video switching hardware, but it's not really something that I expect to see with HDMI switching. Besides, you would want to have the BDP-83's HDMI signal passing through the 997 to get the audio.