What you get here is the four channel quadraphonic mix made for 8-track tapes. This mix was transferred to compact disc for Digital Theater Systems and that's what's been mixed down to two stereo channels here. However, these were done by someone who actually cared about how the final result might sound. It's safe to say there are elements here that are not in the standard stereo mixes and musical details that are buried in the stereo mix. Check it out.
For the very best analysis of the quad version, please see Eight Arms To Hold You.
http://www.lennonstrangedays.com/Eight%20Arms%20To%20Hold%20You.html