Kind of depends...how are you finding the prices on both units that are available to you? The Onkyo with the built in Reon video processor should be much better a upscaling sources than the Faroudja chipse in the Pioneer, but the Pioneer's also seem to be a bit more reliable in terms of bugs as well as producing a lot less heat. Then again, that Onkyo has a monster amp section and power supply compared to just about anything out there in a similar price range.
