I bought this unit to tread water until the whole hd dvd thing settles down. I was a little apprehensive about upconversion but had heard good things about the abilities of the latest units with advanced conversion units like Faroudja. I'm transmitting to a Samsung 1080p lcd monitor.
I have to say with pictures of regular brightness the upscale from 480p is really excellent. No lines, artifacts or weird boundaries. Just a picture with beautiful clarity and contrast. Very HD like. The only significant downfall in it's abilities, and I would argue it is fairly insubstantial, is it's ability to render shades of darker colors in a very dimly lit scene. This is not an lcd thing, it renders blacks very well. What you get in very dark scenes is grainyness in darker areas of the picture, especially areas that are out of focus. It is fairly subtle, but easily pointed out. At the same time this is happening you will get what looks like highlighting in some of the elements of the scene. For example dark hair may take on a bit of a reflective quality. This is pretty noticeable too. Other than that, I have seen no other deficiencies that arise from the player. In your typical movie you won't see these quirks often, if at all. But if you're watching something that is cast in darkness, perhaps Batman or something, it might be prevalent but I would have to check it out.
Overall, I would say that the low price of this upscaling player and the quality with which it handles 95% of pictures, outweighs it's deficiencies. It's a good choice to hold out for the hd dvd war.