I have both - the german 1st edition and the english 2nd edition of the guru book. 1 was a reprint and 2 was a very expensive item on eBay.
It´s a really good book, but don´t expect too much from it. I value the CATS documentation (Commodore Amiga Reference Series, Addison Wesley) more than the Guru Book.
I have the complete series of RKRM's 1st, 2nd and 3rd Editions but none of the CATS stuff.
I rate Ralph's book above the RKRM's in some aspects (Not that I've downloaded the torrent one must understand.

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