Spy and Moonraker seem to have similar outcomes:
-Initial LD release with Dolby Stereo matrix
-THX remaster with different color, and sound coming across different in addition to a 5.1 remix.
-DVD ports
Eventual remasters.
Spy appears to have been redone for the THX series, that has different looking color and the new BD transfer looks like a balance between all sources and much more like the old LD. Arguably the first time it has been properly represented overall. Sound is tricky as it was a stereo release but not Dolby. I believe the mix was re-transferred and perhaps sweetened a bit for the THX process and remixed into 5.1 discrete. The old LD PCM sounds a bit more dirty and has a pop or two. The UE seems to use the same transfer but goes wild with the color and contrast in addition to having even more edge enhancement.
Moonraker has great sound on the original LD with a different looking picture that is terribly noisy on the CLV sides. The sound was remixed for the THX disc, leaving the PCM sounding a bit less robust than the older disc and the 5.1 version is identical. Perhaps they did the remixing and then just had each track finalized out of that? The colors are different when comparing old and THX, but the 4K Lowry image has the finer detail. It seems to have some leanenings of teal here and there and is not as accurate seeming to the source.
What I have really noticed is how different all the THX LDs and their DVD ports come across. In some instances they are appearing to be color and/or contrast boosted or even from a different source (OHMSS). It may very well be that these are not very good references for original presentation.
NSNA:
Everything appears to be the same master. The LD has a WB logo, everything else changes this to Orion. The DVDs are exactly the same, and the BD appears to be a higher generation version of the same source judging from capsaholic. If the LD PCM is added to the BD and a WB opening logo added, that's it.
Note the 5.1 remix is rather poor and the Dolby surround actually has more in the rears, though admittedly not very much. Very poor mix overall, rather mushy in the opening 20 minutes as well. Just compare the title song in the film to CD or vinyl. Huge difference.