To date the oppo 983 is the only player to score a prefect 100% in the tests from the Secrets website.
I have the original oppo 971, a 983 and a PS3.
In my tests the 971 and the PS3 were just about equal in upconversion. The 983 is clearly superior and passes every test on the HQV Benchmark disc.
The oppo BDP-83 uses the same ABT chip as the 983 for de-interlacing and scaling. The 83, after months of beta testing is now in an EAP, (early adoption program). So far 50 units are in the hands of consumers. This past Friday an additional 300 units started shipping. Mine will ship on Monday. So far all reports are that the 83 is at least as good as the 983 for upconversion, with a few comments that the 83 does a better job.
With about a thousand DVD's in my collection it will be an interesting comparison.
The 83 also has a source direct mode which allows it to output whatever is the native format on a disc, allowing those with outboard video processors to play with their toys in pursuit of perfection.
Add SACD, DVD-A, HDCD and other support, my guess is that they will have a hard time keeping up with demand once general release starts.