i think you're right to be cautious fizzy after all nobody's perfect, we all make mistakes. one of the most obvious examples i was made aware of was his 'release' of Weather Report's "Tale Spinnin'" which was patently the Stereo run through his SQ process.
Oh that's interesting ? Sorry you encountered such a deception. Hope you didn't pay too much.
He did have some that were quite good. Hopefully the rest are all legit , as the sources are usually easily obtained by quad members with large collections.