I have all of the Fantasy and OJC CDs, sound is fine throughout. Fantasy had a no-nonsense keep-it-simple approach to recording in the 1950's that worked well. The CDs are 1-to-1 transfers of the tapes. But in some cases you need three discs to complete a session, discographical information is not accurate in many cases, five tracks recorded in stereo are in mono on the CD reissues, and two tracks from singles never were on LP or CD.
The Fantasy SACD reissue of the Tjader/Getz session sounds terrific, btw.