No idea on price. I'm glad to see that such a prouduct is available. Now if I could get one for $199 or less i'd spring for it. Converting progressive-scan DVD to 1080i would be sweet. Not to mention Xbox games.
Converting 480p to 1080i would not look better than 480p, partly because of the interlacing. Also, there are likely doubling artifacts unless it manages to reconstruct the original 24 frames for film-based material then make the 3:2 pulldown 1080i. Not to mention scaling artifacts.
If this is necessary for compatiblity with inputs that only take 1080i, it would be better to use 540p (which the input would take from a timing standpoint).
It's really a shame 1080i exists. It was a compromise to set makers who screamed that the scan rate of 720p would be too costly. Today it is not costly in and of itself, but 3 scan rates costs more than 2 and more material is broadcast in 1080i and 480p, so most sets support those standards.
In a better world the standard would have been 60fps 720p for sports and other video, and 24fps 720p for movies (and sets that would automatically triple this to 72fps 720p).
It may or may not be good. I have a cable box with HDTV output. If I watch non-hdtv channels using the 1080i output, it looks horrible. Maybe this converter does a better job. Let us know if you find out...