I think the Japanese 40th Anniversary Happynet edition is the way to go, PQ is very good although the image is very slightly cropped. It comes in a Black amray which looks very nice also included is an 87-minute documentary (Into The Fire), the theatrical trailer (in HD, though very messy) and an audio interview with Duane Jones. It's all presented in English with Japanese subtitles that can be disabled.
Here are the comparisons of all the official releases:
http://caps-a-holic.com/hd_vergleich...hd_multiID=275
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