Been working my way through the Harry Potter blu rays. I usually only upgrade my DVDs to BR if it's an improvement in SQ (my bdp upscales really well), but as the box set was just 16.99 couldn't resist. I haven't done a side by side comparison of DVD & br, but I watched the first film on DVD a couple of weeks ago. The opening scenes in Privet Drive were a lot clearer (less gloomy than DVD). Quite a surprise. But what is surprising is that you have to wait till film 6 to get a HD soundtrack. Didn't expect it on first few films but thought more would have it.