Personally I think the June 1970 sessions are the best. Over 30 songs in just a couple of days. Although some awesome songs got recorded during the Stax sessions the atmosphere in the studio was down because Elvis was down. After trying out a lot of songs some members of the band had other obligations so some of the Stax mucisians were brought in but they weren't able to play with Elvis because they got the nerves only for being in his presence. It got a little better during the December sessions of the same year.